Transient performance of linear induction launchers fed by generators and by capacitor banks
He, J. L.; Zabar, Z.; Levi, E.; Birenbaum, L.
1991-01-01
Computer simulation is used to investigate the transient performance of induction-type coilguns as a function of the dimensions, material properties, type of supply, firing sequence of switching elements, and connections of drive coils. The performance of both generator-driven and capacitor-driven coilguns is addressed. It is shown that the generator-driven coilgun performs satisfactorily in the starting section. However, at high velocity, the transit time is close to the electrical transient time constant, and therefore the DC components produce a retarding force. To avoid this problem, the three phase voltages should not be switched on simultaneously, but rather phase-by-phase according to their zero current crossing points. The capacitor-driven coilguns derive the alternating current needed to create a traveling wave from resonance with the inductance of the coils. Therefore, the initiation of the sinusoidal current oscillation coincides with the switch-on time. They are ideally suited for short-time, high-acceleration operation, but they are likely to require higher operating voltages than the generator-driven coilguns, because of the constraint imposed on the capacitance by the resonance condition with attenuation.
The research of the staggered lamination linear pulse launcher
宋立伟; 张千帆; 程树康
2004-01-01
This paper proposes a new type of pulse launcher that applies the principle of linear motors. The stator, viz. gun barrel, of the launcher has a new structure of one segment of iron core consisting of 3 staggered laminations. This structure is helpful in advancing the thrust force per volume. Based on introducing the structure and the working principles, this paper resolves the electromagnetic thrusting force and performs mechanical analysis and experiments on the sample launcher. The research shows that this launcher is simple and brushless structure with brief controlling.
Resonant Inductive Power Transfer for Noncontact Launcher-Missile Interface
2016-08-01
implementation of a wireless power transfer system based on the concept of non- radiating inductive coupling. 14. SUBJECT TERMS Resonant Inductive Coupling...link formed by two coupled spiral coils. The first step of the design is the full-wave analysis of a single coil and the evaluation of fundamental...matched layers that absorb any evanescent and radiating field at a large distance from the coil. Note that analytical expressions of the self-impedance
Apparatus for and method of operating a cylindrical pulsed induction mass launcher
Cowan, M. Jr.; Duggin, B.W.; Widner, M.M.
1992-06-30
An electromagnetic cylindrical projectile mass launcher and a method of operation is provided which includes a cylindrical projectile having a conducting armature, a cylindrical barrel in which the armature is received, a plurality of electromagnetic drive coil stages, a plurality of pulse energy sources, and a pulsed power arrangement for generating magnetic pulses forming a pulsed magnetic wave along the length of the launcher barrel. The pulsed magnetic wave provides a propelling force on the projectile along the drive coil. The pulsed magnetic wave of the drive coil stages is advanced along the armature faster than the projectile to thereby generate an induced current wave in the armature. The pulsed generation of the magnetic wave minimizes electromagnetic heating of the projectile and provides for smooth acceleration of the projectile through the barrel of the launcher. 2 figs.
Apparatus for and method of operating a cylindrical pulsed induction mass launcher
Cowan, M. Jr.; Duggin, B.W.; Widner, M.M.
1992-06-30
An electromagnetic cylindrical projectile mass launcher and a method of operation is provided which includes a cylindrical projectile having a conducting armature, a cylindrical barrel in which the armature is received, a plurality of electromagnetic drive coil stages, a plurality of pulse energy sources, and a pulsed power arrangement for generating magnetic pulses forming a pulsed magnetic wave along the length of the launcher barrel. The pulsed magnetic wave provides a propelling force on the projectile along the drive coil. The pulsed magnetic wave of the drive coil stages is advanced along the armature faster than the projectile to thereby generate an induced current wave in the armature. The pulsed generation of the magnetic wave minimizes electromagnetic heating of the projectile and provides for smooth acceleration of the projectile through the barrel of the launcher. 2 figs.
Design and evaluation of coils for a 50 mm diameter induction coilgun launcher
Kaye, R.J.; Shokair, I.R.; Wavrik, R.W. [Sandia National Labs., Albuquerque, NM (United States); Dempsey, J.F.; Honey, W.E.; Shimp, K.J. [EG and G, Inc., Albuquerque, NM (United States); Douglas, G.M. [Rockwell Power Systems Co., Albuquerque, NM (United States)
1993-12-31
Coilguns have the ability to provide magnetic pressure to projectiles which results in near constant acceleration. However, to achieve this performance and control projectile hearing, significant constraints are placed on the design of the coils. We are developing coils to produce an effective projectile base pressure of 100 MPa (1kbar) as a step toward reaching base pressures of 200 MPa. The design uses a scalable technology applicable to the entire range of breech to muzzle coils of a multi-stage launcher. This paper presents the design of capacitor-driven coils for launching nominal 50 mm, 350 gram projectiles. Design criteria, constraints, mechanical stress analysis, launcher performance, and test results are discussed.
Rocket launchers as passive controllers
Cochran, J. E., Jr.; Gunnels, R. T.; McCutchen, R. K., Jr.
1981-12-01
A concept is advanced for using the motion of launchers of a free-flight launcher/rocket system which is caused by random imperfections of the rockets launched from it to reduce the total error caused by the imperfections. This concept is called 'passive launcher control' because no feedback is generated by an active energy source after an error is sensed; only the feedback inherent in the launcher/rocket interaction is used. Relatively simple launcher models with two degrees of freedom, pitch and yaw, were used in conjunction with a more detailed, variable-mass model in a digital simulation code to obtain rocket trajectories with and without thrust misalignment and dynamic imbalance. Angular deviations of rocket velocities and linear deviations of the positions of rocket centers of mass at burnout were computed for cases in which the launcher was allowed to move ('flexible' launcher) and was constrained so that it did not rotate ('rigid' launcher) and ratios of flexible to rigid deviations were determined. Curves of these error ratios versus launcher frequency are presented. These show that a launcher which has a transverse moment of inertia about its pivot point of the same magnitude as that of the centroidal transverse moments of inertia of the rockets launched from it can be tuned to passively reduce the errors caused by rocket imperfections.
1987-03-13
SUBJECT TERMS (Continue on reverse of necessary and dentify by block number) FIEL GRUP SB-GOUP Bipod ’ . Pin tie ~,-,Vehicle-mounted -C~renade launii~r...Fire the parent weapon 20 rounds. (3) Fire launcher 60 rounds. i. Function firings with a launcher on a mount will include extreme left and right...sod, and hard ground. 4.8 ALtLLA.. This test is designed to determine the functioning performance of the test launchers when fired in various
Numerical analysis method for linear induction machines.
Elliott, D. G.
1972-01-01
A numerical analysis method has been developed for linear induction machines such as liquid metal MHD pumps and generators and linear motors. Arbitrary phase currents or voltages can be specified and the moving conductor can have arbitrary velocity and conductivity variations from point to point. The moving conductor is divided into a mesh and coefficients are calculated for the voltage induced at each mesh point by unit current at every other mesh point. Combining the coefficients with the mesh resistances yields a set of simultaneous equations which are solved for the unknown currents.
Emittance Growth in Linear Induction Accelerators
Ekdahl, Carl
2017-01-01
The Dual-Axis Radiographic Hydrotest (DARHT) facility uses bremsstrahlung radiation source spots produced by the focused electron beams from two linear induction accelerators (LIAs) to radiograph large hydrodynamic experiments driven by high explosives. Radiographic resolution is determined by the size of the source spot, and beam emittance is the ultimate limitation to spot size. Some of the possible causes for the emittance growth in the DARHT LIA have been investigated using particle-in-ce...
Linear induction accelerator for heavy ions
Keefe, D.
1976-09-01
There is considerable recent interest in the use of high energy (..gamma.. = 1.1), heavy (A greater than or equal to 100) ions to irradiate deuterium--tritium pellets in a reactor vessel to constitute a power source at the level of 1 GW or more. Various accelerator configurations involving storage rings have been suggested. A discussion is given of how the technology of Linear Induction Accelerators--well known to be matched to high current and short pulse length--may offer significant advantages for this application.
Emittance growth in linear induction accelerators
Ekdahl, C A; Schulze, M E; Carlson, C A; Frayer, D K; Mostrum, C; Thoma, C H
2014-01-01
The Dual-Axis Radiographic Hydrotest (DARHT) facility uses bremsstrahlung radiation source spots produced by the focused electron beams from two linear induction accelerators (LIAs) to radiograph large hydrodynamic experiments driven by high explosives. Radiographic resolution is determined by the size of the source spot, and beam emittance is the ultimate limitation to spot size. On the DARHT Axis-II LIA we measure an emittance higher than predicted by theoretical simulations, and even though this axis produces sub-millimeter source spots, we are exploring ways to improve the emittance. Some of the possible causes for the discrepancy have been investigated using particle-in-cell (PIC) codes, although most of these are discounted based on beam measurements. The most likely source of emittance growth is a mismatch of the beam to the magnetic transport, which can cause beam halo.
Dynamic Model of Linear Induction Motor Considering the End Effects
H. A. Hairik
2009-01-01
Full Text Available In this paper the dynamic behavior of linear induction motor is described by a mathematical model taking into account the end effects and the core losses. The need for such a model rises due to the complexity of linear induction motors electromagnetic field theory. The end affects by introducing speed dependent scale factor to the magnetizing inductance and series resistance in the d-axis equivalent circuit. Simulation results are presented to show the validity of the model during both no-load and sudden load change intervals. This model can also be used directly in simulation researches for linear induction motor vector control drive systems.
Investigation Into Non-Symmetrical Modes Of Linear Induction Motors
Lisauskas, Saulius
2007-01-01
Linear induction motors are applied in equipments with different requirements set up to the controlled motion parameters. Investigation of motoring and breaking modes remains the relevant problem nowadays. The scientific novelty is based on analysis of non-symmetrical operation modes of linear induction motor at supplying it by a voltage source, developing a generalized model of motoring and breaking dynamic modes and analyzing influence of linear motor windings connection way and contro...
Linearizing Control of Induction Motor Based on Networked Control Systems
Jun Ren; Chun-Wen Li; De-Zong Zhao
2009-01-01
A new approach to speed control of induction motors is developed by introducing networked control systems (NCSs) into the induction motor driving system. The control strategy is to stabilize and track the rotor speed of the induction motor when the network time delay occurs in the transport medium of network data. First, a feedback linearization method is used to achieve input-output linearization and decoupling control of the induction motor driving system based on rotor flux model, and then the characteristic of network data is analyzed in terms of the inherent network time delay. A networked control model of an induction motor is established. The sufficient condition of asymptotic stability for the networked induction motor driving system is given, and the state feedback controller is obtained by solving the linear matrix inequalities (LMIs). Simulation results verify the efficiency of the proposed scheme.
A model of annular linear induction pumps
Momozaki, Yoichi [Argonne National Lab. (ANL), Argonne, IL (United States)
2016-10-27
The present work explains how the magnetic field and the induced current are obtained when the distributed coils are powered by a 3 phase power supply. From the magnetic field and the induced current, the thrust and the induction losses in the pump can be calculated to estimate the pump performance.
Linear Parameter Varying Control of Induction Motors
Trangbæk, Klaus
for high performance applications. This thesis demonstrates how LPV control theory provides a systematic way to achieve good performance for these problems. The main contributions of this thesis are the application of the LPV control theory to induction motor control as well as various contributions...... to the field of LPV control theory itself...
Kolm, H.; Mongeau, P.; Williams, F.
1980-09-01
Recent advances in energy storage, switching and magnet technology make electromagnetic acceleration a viable alternative to chemical propulsion for certain tasks, and a means to perform other tasks not previously feasible. Applications include the acceleration of gram-size particles for hypervelocity research and the initiation of fusion by impact, a replacement for chemically propelled artillery, the transportation of cargo and personnel over inaccessible terrain, and the launching of space vehicles to supply massive space operations, and for the disposal of nuclear waste. The simplest launcher of interest is the railgun, in which a short-circuit slide or an arc is driven along two rails by direct current. The most sophisticated studied thus far is the mass driver, in which a superconducting shuttle bucket is accelerated by a line of pulse coils energized by capacitors at energy conversion efficiencies better than 90%. Other accelerators of interest include helical, brush-commutated motors, discrete coil arc commutated drivers, flux compression momentum transformers, and various hybrid electrochemical devices.
Robust linear parameter varying induction motor control with polytopic models
Dalila Khamari
2013-01-01
Full Text Available This paper deals with a robust controller for an induction motor which is represented as a linear parameter varying systems. To do so linear matrix inequality (LMI based approach and robust Lyapunov feedback controller are associated. This new approach is related to the fact that the synthesis of a linear parameter varying (LPV feedback controller for the inner loop take into account rotor resistance and mechanical speed as varying parameter. An LPV flux observer is also synthesized to estimate rotor flux providing reference to cited above regulator. The induction motor is described as a polytopic model because of speed and rotor resistance affine dependence their values can be estimated on line during systems operations. The simulation results are presented to confirm the effectiveness of the proposed approach where robustness stability and high performances have been achieved over the entire operating range of the induction motor.
Linear Parameter Varying Control of Doubly Fed Induction Machines
Tien, H. Nguyen; Scherer, Carsten W.; Scherpen, Jacquelien M.A.; Müller, Volkmar
2016-01-01
This paper is concerned with the design of a self-scheduled current controller for doubly fed induction machines. The design is based on the framework of linear parameter-varying systems where the mechanical angular speed is considered to be a measurable time-varying parameter. The objective is to o
Li, Dong; Wen, Yinghong; Li, Weili; Fang, Jin; Cao, Junci; Zhang, Xiaochen; Lv, Gang
2017-03-01
In the paper, the numerical method calculating asymmetric primary slot leakage inductances of Single-sided High-Temperature Superconducting (HTS) Linear Induction Motor (HTS LIM) is presented. The mathematical and geometric models of three-dimensional nonlinear transient electromagnetic field are established and the boundary conditions are also given. The established model is solved by time-stepping Finite Element Method (FEM). Then, the three-phase asymmetric primary slot leakage inductances under different operation conditions are calculated by using the obtained electromagnetic field distribution. The influences of the special effects such as longitudinal end effects, transversal edge effects, etc. on the primary slot leakage inductance are investigated. The presented numerical method is validated by experiments carried out on a 3.5 kW prototype with copper wires which has the same structures with the HTS LIM.
Low-inductance gas switches for linear transformer drivers
J. R. Woodworth
2009-06-01
Full Text Available We are investigating several alternate gas-switch designs for use in linear transformer drivers. To meet linear-transformer-driver (LTD requirements, these air-insulated switches must be DC charged to 200 kV, be triggerable with a jitter of 5 ns or less, have very low prefire and no-fire rates (∼1 in 10^{4} shots, and have a lifetime of at least several thousand shots. Since the switch inductance plays a significant role in limiting the rise time and peak current of the LTD circuit, the inductance needs to be as low as possible. The switches are required to conduct current pulses with ∼100-ns rise times and 20–80 kA peak currents, depending on the application. Our baseline switch, designed by the High Current Electronics Institute in Tomsk, Russia, is a six-stage switch with an inductance on the order of 115 nH that is insulated with 47–67 psia of air. We are also testing three smaller two-stage switches that have inductances on the order of 66–100 nH. The smaller switches are insulated with 92–252 psia of air.
Direct torque control with feedback linearization for induction motor drives
Lascu, Cristian; Jafarzadeh, Saeed; Fadali, Sami M.
2015-01-01
This paper describes a Direct Torque Controlled (DTC) Induction Machine (IM) drive that employs feedback linearization and sliding-mode control. A feedback linearization approach is investigated, which yields a decoupled linear IM model with two state variables: torque and stator flux magnitude...... of the sliding surface. The VSC component assures robustness as in DTC, while the proportional component eliminates the torque and flux ripple. The torque time response is similar to DTC and the proposed solution is flexible and highly tunable due to the proportional controller. The controller design and its...... robust stability analysis are presented. The sliding controller is compared with a linear DTC scheme, and experimental results for a sensorless IM drive validate the proposed solution....
Direct Torque Control With Feedback Linearization for Induction Motor Drives
Lascu, Cristian Vaslie; Jafarzadeh, Saeed; Fadali, Sami M.
2017-01-01
This paper describes a direct-torque-controlled (DTC) induction motor (IM) drive that employs feedback linearization and sliding-mode control (SMC). A new feedback linearization approach is proposed, which yields a decoupled linear IM model with two state variables: torque and stator flux magnitude....... This intuitive linear model is used to implement a DTC-type controller that preserves all DTC advantages and eliminates its main drawback, the flux and torque ripple. Robust, fast, and ripple-free control is achieved by using SMC with proportional control in the vicinity of the sliding surface. SMC assures...... robustness as in DTC, while the proportional component eliminates the torque and flux ripple. The torque time response is similar to conventional DTC and the proposed solution is flexible and highly tunable due to the P component. The controller design is presented, and its robust stability is analyzed...
NEW PUNCHING MACHINE DRIVEN BY LINEAR INDUCTION MOTOR
无
2000-01-01
The research and application of the punching machine driven by a linear induction motor(LIM)are introducedThe fundamental principle,construction,performance and application are describedComparing this new model machine with its traditional form,the LIM driven punching machine has many great advantages,such as,simple construction,small size and mass,low production cost,short production time,easy to control,low noise and considerable energy saving
杨成伟; 李小将; 武昊然
2013-01-01
The inductance gradient is one of the important indexes affecting rail launcher performance. For rail launcher inductance gradient many influence factors, carries on the reasonable design can make the railgun performance to achieve optimal results. A rectangular cross-sectional rail launcher model was built based on the Biot-Savart law in this paper. Furthermore, the analytical expression of inductance gradient can be obtained by this model. The single parameter sensitivity analysis method was employed to analyze several factors of the inductance gradient. The result shows that:compared with common methods, this paper performs well in both the height and the space between rails;the reason why it is different in the factor of thickness is shown. The armature position which regarded as one of the factors is introduced in the analytical expression of inductance gradient, and some details are done to explain how does it affects. This can provide reference for future design.%电感梯度是影响轨道发射器性能的重要指标之一，针对轨道发射器电感梯度影响因素众多的问题，对其进行合理的设计能够使轨道炮性能达到优化的效果，从毕奥-萨法尔定律出发，建立了矩形截面轨道发射器模型并求得电感梯度解析表达式；运用单参数灵敏度方法对模型中几种影响因素进行仿真分析并与常见电感梯度计算方法进行对比。结果表明：与常规计算电感梯度方法相比，该模型结果较为理想，验证了准确性；与常规方法的不同点在于引入电枢位置作为电感梯度影响因素之一并说明其影响方式。该研究可为轨道发射器设计提供一定参考。
NASTRAN buckling study of a linear induction motor reaction rail
Williams, J. G.
1973-01-01
NASTRAN was used to study problems associated with the installation of a linear induction motor reaction rail test track. Specific problems studied include determination of the critical axial compressive buckling stress and establishment of the lateral stiffness of the reaction rail under combined loads. NASTRAN results were compared with experimentally obtained values and satisfactory agreement was obtained. The reaction rail was found to buckle at an axial compressive stress of 11,400 pounds per square inch. The results of this investigation were used to select procedures for installation of the reaction rail.
Misron, Norhisam; Ying, Loo Qian; Firdaus, Raja Nor; Abdullah, Norrimah; Mailah, Nashiren Farzilah; Wakiwaka, Hiroyuki
2011-01-01
This paper discusses the effect of inductive coil shape on the sensing performance of a linear displacement sensor. The linear displacement sensor consists of a thin type inductive coil with a thin pattern guide, thus being suitable for tiny space applications. The position can be detected by measuring the inductance of the inductive coil. At each position due to the change in inductive coil area facing the pattern guide the value of inductance is different. Therefore, the objective of this research is to study various inductive coil pattern shapes and to propose the pattern that can achieve good sensing performance. Various shapes of meander, triangular type meander, square and circle shape with different turn number of inductive coils are examined in this study. The inductance is measured with the sensor sensitivity and linearity as a performance evaluation parameter of the sensor. In conclusion, each inductive coil shape has its own advantages and disadvantages. For instance, the circle shape inductive coil produces high sensitivity with a low linearity response. Meanwhile, the square shape inductive coil has a medium sensitivity with higher linearity.
Development of a linear induction motor based artificial muscle system.
Gruber, A; Arguello, E; Silva, R
2013-01-01
We present the design of a linear induction motor based on electromagnetic interactions. The engine is capable of producing a linear movement from electricity. The design consists of stators arranged in parallel, which produce a magnetic field sufficient to displace a plunger along its axial axis. Furthermore, the winding has a shell and cap of ferromagnetic material that amplifies the magnetic field. This produces a force along the length of the motor that is similar to that of skeletal muscle. In principle, the objective is to use the engine in the development of an artificial muscle system for prosthetic applications, but it could have multiple applications, not only in the medical field, but in other industries.
A Differential Monolithically Integrated Inductive Linear Displacement Measurement Microsystem
Matija Podhraški
2016-03-01
Full Text Available An inductive linear displacement measurement microsystem realized as a monolithic Application-Specific Integrated Circuit (ASIC is presented. The system comprises integrated microtransformers as sensing elements, and analog front-end electronics for signal processing and demodulation, both jointly fabricated in a conventional commercially available four-metal 350-nm CMOS process. The key novelty of the presented system is its full integration, straightforward fabrication, and ease of application, requiring no external light or magnetic field source. Such systems therefore have the possibility of substituting certain conventional position encoder types. The microtransformers are excited by an AC signal in MHz range. The displacement information is modulated into the AC signal by a metal grating scale placed over the microsystem, employing a differential measurement principle. Homodyne mixing is used for the demodulation of the scale displacement information, returned by the ASIC as a DC signal in two quadrature channels allowing the determination of linear position of the target scale. The microsystem design, simulations, and characterization are presented. Various system operating conditions such as frequency, phase, target scale material and distance have been experimentally evaluated. The best results have been achieved at 4 MHz, demonstrating a linear resolution of 20 µm with steel and copper scale, having respective sensitivities of 0.71 V/mm and 0.99 V/mm.
A Differential Monolithically Integrated Inductive Linear Displacement Measurement Microsystem.
Podhraški, Matija; Trontelj, Janez
2016-03-17
An inductive linear displacement measurement microsystem realized as a monolithic Application-Specific Integrated Circuit (ASIC) is presented. The system comprises integrated microtransformers as sensing elements, and analog front-end electronics for signal processing and demodulation, both jointly fabricated in a conventional commercially available four-metal 350-nm CMOS process. The key novelty of the presented system is its full integration, straightforward fabrication, and ease of application, requiring no external light or magnetic field source. Such systems therefore have the possibility of substituting certain conventional position encoder types. The microtransformers are excited by an AC signal in MHz range. The displacement information is modulated into the AC signal by a metal grating scale placed over the microsystem, employing a differential measurement principle. Homodyne mixing is used for the demodulation of the scale displacement information, returned by the ASIC as a DC signal in two quadrature channels allowing the determination of linear position of the target scale. The microsystem design, simulations, and characterization are presented. Various system operating conditions such as frequency, phase, target scale material and distance have been experimentally evaluated. The best results have been achieved at 4 MHz, demonstrating a linear resolution of 20 µm with steel and copper scale, having respective sensitivities of 0.71 V/mm and 0.99 V/mm.
A Differential Monolithically Integrated Inductive Linear Displacement Measurement Microsystem
Podhraški, Matija; Trontelj, Janez
2016-01-01
An inductive linear displacement measurement microsystem realized as a monolithic Application-Specific Integrated Circuit (ASIC) is presented. The system comprises integrated microtransformers as sensing elements, and analog front-end electronics for signal processing and demodulation, both jointly fabricated in a conventional commercially available four-metal 350-nm CMOS process. The key novelty of the presented system is its full integration, straightforward fabrication, and ease of application, requiring no external light or magnetic field source. Such systems therefore have the possibility of substituting certain conventional position encoder types. The microtransformers are excited by an AC signal in MHz range. The displacement information is modulated into the AC signal by a metal grating scale placed over the microsystem, employing a differential measurement principle. Homodyne mixing is used for the demodulation of the scale displacement information, returned by the ASIC as a DC signal in two quadrature channels allowing the determination of linear position of the target scale. The microsystem design, simulations, and characterization are presented. Various system operating conditions such as frequency, phase, target scale material and distance have been experimentally evaluated. The best results have been achieved at 4 MHz, demonstrating a linear resolution of 20 µm with steel and copper scale, having respective sensitivities of 0.71 V/mm and 0.99 V/mm. PMID:26999146
Dynamic Performance of Subway Vehicle with Linear Induction Motor System
Wu, Pingbo; Luo, Ren; Hu, Yan; Zeng, Jing
The light rail vehicle with Linear Induction Motor (LIM) bogie, which is a new type of urban rail traffic tool, has the advantages of low costs, wide applicability, low noise, simple maintenance and better dynamic behavior. This kind of vehicle, supported and guided by the wheel and rail, is not driven by the wheel/rail adhesion force, but driven by the electromagnetic force between LIM and reaction plate. In this paper, three different types of suspensions and their characteristic are discussed with considering the interactions both between wheel and rail and between LIM and reaction plate. A nonlinear mathematical model of the vehicle with LIM bogie is set up by using the software SIMPACK, and the electromechanical model is also set up on Simulink roof. Then the running behavior of the LIM vehicle is simulated, and the influence of suspension on the vehicle dynamic performance is investigated.
Recent advances in kicker pulser technology for linear induction accelerators
Chen, Y J; Cook, E; Davis, B; Dehope, W J; Yen, B
1999-06-01
Recent progress in the development and understanding of linear induction accelerator have produced machines with 10s of MeV of beam energy and multi-kiloampere currents. Near-term machines, such as DARHT-2, are envisioned with microsecond pulselengths. Fast beam kickers, based on cylindrical electromagnetic stripline structures, will permit effective use of these extremely high-energy beams in an increasing number of applications. In one application, radiography, kickers were an essential element in resolving temporal evolution of hydrodynamic events by cleaving out individual pulses from long, microsecond beams. Advanced schemes are envisioned where these individual pulses are redirected through varying length beam lines and suitably recombined for stereographic imaging or tomographic reconstruction. Recent advances in fast kickers and their pulsed power technology are described. Kicker pulsers based on both planar triode and all solid-state componentry are discussed and future development plans are presented.
Beam dynamics in a long-pulse linear induction accelerator
Ekdahl, Carl [Los Alamos National Laboratory; Abeyta, Epifanio O [Los Alamos National Laboratory; Aragon, Paul [Los Alamos National Laboratory; Archuleta, Rita [Los Alamos National Laboratory; Cook, Gerald [Los Alamos National Laboratory; Dalmas, Dale [Los Alamos National Laboratory; Esquibel, Kevin [Los Alamos National Laboratory; Gallegos, Robert A [Los Alamos National Laboratory; Garnett, Robert [Los Alamos National Laboratory; Harrison, James F [Los Alamos National Laboratory; Johnson, Jeffrey B [Los Alamos National Laboratory; Jacquez, Edward B [Los Alamos National Laboratory; Mc Cuistian, Brian T [Los Alamos National Laboratory; Montoya, Nicholas A [Los Alamos National Laboratory; Nath, Subrato [Los Alamos National Laboratory; Nielsen, Kurt [Los Alamos National Laboratory; Oro, David [Los Alamos National Laboratory; Prichard, Benjamin [Los Alamos National Laboratory; Rose, Chris R [Los Alamos National Laboratory; Sanchez, Manolito [Los Alamos National Laboratory; Schauer, Martin M [Los Alamos National Laboratory; Seitz, Gerald [Los Alamos National Laboratory; Schulze, Martin [Los Alamos National Laboratory; Bender, Howard A [Los Alamos National Laboratory; Broste, William B [Los Alamos National Laboratory; Carlson, Carl A [Los Alamos National Laboratory; Frayer, Daniel K [Los Alamos National Laboratory; Johnson, Douglas E [Los Alamos National Laboratory; Tom, C Y [Los Alamos National Laboratory; Trainham, C [Los Alamos National Laboratory; Williams, John [Los Alamos National Laboratory; Scarpetti, Raymond [LLNL; Genoni, Thomas [VOSS; Hughes, Thomas [VOSS; Toma, Carsten [VOSS
2010-01-01
The second axis of the Dual Axis Radiography of Hydrodynamic Testing (DARHT) facility produces up to four radiographs within an interval of 1.6 microseconds. It accomplishes this by slicing four micro-pulses out of a long 1.8-kA, 16.5-MeV electron beam pulse and focusing them onto a bremsstrahlung converter target. The long beam pulse is created by a dispenser cathode diode and accelerated by the unique DARHT Axis-II linear induction accelerator (LIA). Beam motion in the accelerator would be a problem for radiography. High frequency motion, such as from beam breakup instability, would blur the individual spots. Low frequency motion, such as produced by pulsed power variation, would produce spot to spot differences. In this article, we describe these sources of beam motion, and the measures we have taken to minimize it.
Multipurpose 5-MeV linear induction accelerator
Birx, D.L.; Hawkins, S.A.; Poor, S.E.; Reginato, L.L. Smith, M.W.
1984-06-11
Although linear induction accelerators (LIAs) are quite reliable by most standards, they are limited in repeating rate, average power, and reliability because the final stage of energy delivery is based on spark gap performance. In addition, they have a low duty factor of operation. To provide a higher burst rate and greater reliability, the researchers used new technology to develop a magnetic pulse compression scheme that eliminates all spark gaps and exceeds requirements. The paper describes the scheme. The magnetic drive system can be tailored to drive induction cells from a few kA to over 10 kA at 500 kV, with average beam power levels in the megawatts. This new 5-MeV, 2.5-kA LIA under construction at the Lawrence Livermore National Laboratory (LLNL) will be used for the development of high brightness sources and will provide a test bed for the new technology, which should lead to LIAs that surpass the radio frequency linacs for efficiency and reliability, as well as fit other industrial applications, such as sewage sterilization.
Multipurpose 5-MeV linear induction accelerator
Birx, D. L.; Hawkins, S. A.; Poor, S. E.; Reginato, L. L.; Smith, M. W.
1984-06-01
Although linear induction accelerators (LIAs) are quite reliable by most standards, they are limited in repeating rate, average power, and reliability because the final stage of energy delivery is based on spark gap performance. In addition, they have a low duty factor of operation. To provide a higher burst rate and greater reliability, new technology was used to develop a magnetic pulse compression scheme that eliminates all spark gaps and exceeds requirements. The magnetic drive system are tailored to drive induction cells from a few kA to over 10 kA at 500 kV, with average beam power levels in the megawatts. This new 5-MeV, 2.5-kA LIA under construction at the Lawrence Livermore National Laboratory (LLNL) will be used for the development of high brightness sources and will provide a test bed for the new technology, which should lead to LIAs that surpass the radio frequency linacs for efficiency and reliability, as well as fit other industrial applications, such as sewage sterilization.
Tuning the DARHT Axis-II linear induction accelerator focusing
Ekdahl, Carl A. [Los Alamos National Laboratory
2012-04-24
Flash radiography of large hydrodynamic experiments driven by high explosives is a well-known diagnostic technique in use at many laboratories, and the Dual-Axis Radiography for Hydrodynamic Testing (DARHT) facility at Los Alamos produces flash radiographs of large hydrodynamic experiments. Two linear induction accelerators (LIAs) make the bremsstrahlung radiographic source spots for orthogonal views of each test. The 2-kA, 20-MeV Axis-I LIA creates a single 60-ns radiography pulse. The 1.7-kA, 16.5-MeV Axis-II LIA creates up to four radiography pulses by kicking them out of a longer pulse that has a 1.6-{mu}s flattop. The Axis-II injector, LIA, kicker, and downstream transport (DST) to the bremsstrahlung converter are described. Adjusting the magnetic focusing and steering elements to optimize the electron-beam transport through an LIA is often called 'tuning.' As in all high-current LIAs, the focusing field is designed to be as close to that of the ideal continuous solenoid as physically possible. In ideal continuous solenoidal transport a smoothly varying beam size can easily be found for which radial forces balance, and the beam is said to be 'matched' to the focusing field. A 'mismatched' beam exhibits unwanted oscillations in size, which are a source of free energy that contributes to emittance growth. This is undesirable, because in the absence of beam-target effects, the radiographic spot size is proportional to the emittance. Tuning the Axis-II LIA is done in two steps. First, the solenoidal focusing elements are set to values designed to provide a matched beam with little or no envelope oscillations, and little or no beam-breakup (BBU) instability growth. Then, steering elements are adjusted to minimize the motion of the centroid of a well-centered beam at the LIA exit. This article only describes the design of the tune for the focusing solenoids. The DARHT Axis-II LIA was required to be re-tuned after installing an
Coilgun Launcher for Nanosatellites
Turman, B.N.
1999-03-23
Nanosatellite space launches could significantly benefit from an electrically powered launch complex, based on an electromagnetic coil launcher. This paper presents results of studies to estimate the required launcher parameters and some fixed facility issues. This study is based on electromagnetic launch, or electromagnetic gun technology, which is constrained to a coaxial geometry to take advantage of the efficiency of closely-coupled coils. A baseline configuration for analysis considers a payload mass of 10 kg, launch velocity of 6 km/s, a second stage solid booster for orbital insertion, and a payload fraction of about 0.1. The launch facility is envisioned as an inclined track, 1-2 km in length, mounted on a hillside at 25 degrees aimed in the orbital inclination of interest. The launcher energy and power requirements fall in the range of 2000 MJ and 2 MW electric. This energy would be supplied by 400 modules of energy storage and magnetic coils. With a prime power generator of 2 MW, a launch rate of some 200 satellites per day is possible. The launch requires high acceleration, so the satellite package must be hardened to launch acceleration on the order of 1000 gee. Parametric evaluations compare performance parameters for a launcher length of 1-2 km, exit velocity of 4-8 km/s, and payloads of 1-100 kg. The EM launch complex could greatly reduce the amount of fuels handling, reduce the turn-around time between launches, allow more concurrence in launch preparation, reduce the manpower requirements for launch vehicle preparation and increase the reliability of launch by using more standardized vehicle preparations. Most importantly, such a facility could reduce the cost per launch and could give true launch-on-demand capability for nanosatellites.
Non-US electrodynamic launchers research and development
Parker, J.V.; Batteh, J.H.; Greig, J.R.; Keefer, D.; McNab, I.R.; Zabar, Z.
1994-11-01
Electrodynamic launcher research and development work of scientists outside the United States is analyzed and assessed by six internationally recognized US experts in the field of electromagnetic and electrothermal launchers. The assessment covers five broad technology areas: (1) Experimental railguns; (2) Railgun theory and design; (3) Induction launchers; (4) Electrothermal guns; (5) Energy storage and power supplies. The overall conclusion is that non-US work on electrodynamic launchers is maturing rapidly after a relatively late start in many countries. No foreign program challenges the US efforts in scope, but it is evident that the United States may be surpassed in some technologies within the next few years. Until recently, published Russian work focused on hypervelocity for research purposes. Within the last two years, large facilities have been described where military-oriented development has been underway since the mid-1980s. Financial support for these large facilities appears to have collapsed, leaving no effective effort to develop practical launchers for military or civilian applications. Electrodynamic launcher research in Europe is making rapid progress by focusing on a single application, tactical launchers for the military. Four major laboratories, in Britain, France, Germany, and the Netherlands, are working on this problem. Though narrower in scope than the US effort, the European work enjoys a continuity of support that has accelerated its progress. The next decade will see the deployment of electrodynamic launcher technology, probably in the form of an electrothermal-chemical upgrade for an existing gun system. The time scale for deployment of electromagnetic launchers is entirely dependent on the level of research-and-development effort. If resources remain limited, the advantage will lie with cooperative efforts that have reasonably stable funding such as the present French-German program.
Effects of Linear Induction Motor Parameters in Its Optimum Design Based on Finite Element Method
Mehrdad JafarBoland; AbdolAmir Nekoubin
2009-01-01
Effective parameters in performance of linear induction motors such as air gap, number of poles and the thickness of secondary must be selected and optimized to increase power coefficients and motor performance significantly. In this paper a double sided linear induction motor in different conditions is designed and next by finite element method analyzed. Then for comparing analytical model and numerical model a linear motor using Matlab software is simulated in different condition. It is cle...
Electrostatic Climber for Space Elevator and Launcher
Bolonkin, A
2007-01-01
Author details research on the new, very prospective, electrostatic Space Elevator climber based on a new electrostatic linear engine previously offered at the 42nd Joint Propulsion Conference (AIAA-2006-5229) and published in AEAT, Vol.78, No.6, 2006, pp. 502-508. The electrostatic climber discussed can have any speed (and braking), the energy for climber movement is delivered by a lightweight high-voltage line into a Space Elevator-holding cable from Earth electric generator. This electric line also can be used for delivery electric energy to a Geosynchronous Space Station. At present, the best solution of the climber problem (announced by NASA as one important awarding problem of Space Elevator) is problematic. Author also shows the linear electrostatic engine may be used as realistic power space launcher at the present time. Two projects illustrate these new devices. Key words: Space elevator, Electrostatic climber for space elevator, Electrostatic space launcher, Electrostatic accelerator. This work is p...
Electromagnetic Launchers and Guns. Phase 1
1980-06-01
a high-speed maglev transportation system based on a linear synchronous motor (1,2,3). In 1975 Gerard K. O’Neill of Princeton University...fact that the very important railgun- homopolar launcher technology is already being pursued at Westinghouse and university of Texas, Austin. The...shown in Fig. 14 on the following page. There are three comparable options for energy storage: an engine-driven homopolar generator followed by an
Exact linearization of an induction machine with rotoric flux orientation
Bentaallah Abderrahim
2008-01-01
Full Text Available In this paper, we present the linearization control of an asynchronous machine. It allows decoupling and linearization of the system without including flux orientation. This non-linear control (NLC applied to the asynchronous machine breaks up the system into two linear and independent mono systems. The speed and the Id current controls are carried out by traditional regulators PI. A qualitative analysis of the evolution of the principal variables describing the behaviour of the global system (IM-control and its robustness is developed by several tests of digital simulation in the final stage. Numerous tests have been performed under Simulink/Matlab to show the control system performances.
Magnetic reconnection launcher
Cowan, M.
1987-04-06
An electromagnetic launcher includes a plurality of electrical stages which are energized sequentially in the launcher with the passage of a projectiles. Each stage of the launcher includes two or more coils which are arranged coaxially on either closed-loop or straight lines to form gaps between their ends. The projectile has an electrically conductive gap-portion that passes through all the gaps of all the stages in a direction transverse to the axes of the coils. The coils receive an electric current, store magnetic energy, and convert a significant portion of the stored magnetic energy into kinetic energy of the projectile moves through the gap. The magnetic polarity of the opposing coils is in the same direction, e.g. N-S-N-S. A gap portion of the projectile may be made from aluminum and is propelled by the reconnection of magnetic flux stored in the coils which causes accelerating forces to act upon the projectile and at the horizontal surfaces of the projectile near its rear. The gap portion of the projectile may be flat, rectangular and longer than the length of the opposing coils. The gap portion of the projectile permits substantially unrestricted distribution of the induced currents so that current densities are only high where the useful magnetic force is high. This allows designs which permit ohmic oblation from the rear surfaces of the gap portion of the projectile allowing much high velocities to be achieved. An electric power apparatus controls the electric power supplied to the opposing coils until the gap portion of the projectile substantially occupies the gap between the coils, at which time the coils are supplied with peak current quickly. 8 figs.
Jun Di; Yu Fan; Yajing Liu; Sijia Liu; Yulong Zhu
2017-01-01
In this paper, we propose a novel variable pole pitch (VPP) electromagnetic (EM) propulsion technique using a series of ladder-slot-secondary double-sided linear induction motors (LS-secondary DLIMs...
The time and space characteristics of magnetomotive force in the cascaded linear induction motor
Dajing Zhou Jiaqing Ma Lifeng Zhao Xiao Wan Yong Zhang Yong Zhao
2013-01-01
To choose a reasonable mode of three-phase winding for the improvement of the operating efficiency of cascaded linear induction motor, the time and space characteristics of magnetomotive force were investigated...
MAGNETIC INDUCTION DISTRIBUTION IN A LINEAR SYNCHRONUS MOTOR WITH MAGNETIC SUSPENSION
D.I. Parkhomenko
2013-02-01
Full Text Available Results of computer simulation and experimental investigations of magnetic induction distribution in a coaxial linear synchronous motor with magnetic suspension are presented. The magnetic induction distribution has been studied both in the motor air gap and on the runner surface.
В.Т. Чемерис
2006-04-01
Full Text Available There is a method of simplified calculation and design parameters choice elaborated in this article with corresponding basing for the induction system of electron-beam sterilizer on the base of linear induction accelerator taking into account the parameters of magnetic material for production of cores and parameters of pulsed voltage.
Note: A pulsed laser ion source for linear induction accelerators
Zhang, H., E-mail: bamboobbu@hotmail.com [Institute of Fluid Physics, China Academy of Engineering Physics, P.O. Box 919-106, Mianyang 621900 (China); School of Physics, Peking University, Beijing 100871 (China); Zhang, K.; Shen, Y.; Jiang, X.; Dong, P.; Liu, Y.; Wang, Y.; Chen, D.; Pan, H.; Wang, W.; Jiang, W.; Long, J.; Xia, L.; Shi, J.; Zhang, L.; Deng, J. [Institute of Fluid Physics, China Academy of Engineering Physics, P.O. Box 919-106, Mianyang 621900 (China)
2015-01-15
We have developed a high-current laser ion source for induction accelerators. A copper target was irradiated by a frequency-quadrupled Nd:YAG laser (266 nm) with relatively low intensities of 10{sup 8} W/cm{sup 2}. The laser-produced plasma supplied a large number of Cu{sup +} ions (∼10{sup 12} ions/pulse) during several microseconds. Emission spectra of the plasma were observed and the calculated electron temperature was about 1 eV. An induction voltage adder extracted high-current ion beams over 0.5 A/cm{sup 2} from a plasma-prefilled gap. The normalized beam emittance measured by a pepper-pot method was smaller than 1 π mm mrad.
Effects of Linear Induction Motor Parameters in Its Optimum Design Based on Finite Element Method
Mehrdad JafarBoland
2009-03-01
Full Text Available Effective parameters in performance of linear induction motors such as air gap, number of poles and the thickness of secondary must be selected and optimized to increase power coefficients and motor performance significantly. In this paper a double sided linear induction motor in different conditions is designed and next by finite element method analyzed. Then for comparing analytical model and numerical model a linear motor using Matlab software is simulated in different condition. It is clear from the results that with optimal value of effective parameters, power losses decreased the performance of motor is improved and efficiency of linear motor is increased.
BBU design of linear induction accelerator cells for radiography application
Shang, C.C.; Chen, Y.J.; Gaporaso, G.J.; Houck, T.L.; Molau, N.E.; Focklen, J.; Gregory, S.
1997-05-06
There is an ongoing effort to develop accelerating modules for high-current electron accelerators for advanced radiography application. Accelerating modules with low beam-cavity coupling impedances along with gap designs with acceptable field stresses comprise a set of fundamental design criteria. We examine improved cell designs which have been developed for accelerator application in several radiographic operating regimes. We evaluate interaction impedances, analyze the effects of beam structure coupling on beam dynamics (beam break-up instability and corkscrew motion). We also provide estimates of coupling through interesting new high-gradient insulators and evaluate their potential future application in induction cells.
MODELLING AND CONTROLLING OF INDUCTION MOTOR BY USING LINEAR ADRC
CH. NAGA KOTI KUMAR,
2011-04-01
Full Text Available In this paper we present a new novel approach for the speed control of an IM using Linear Active Disturbance Rejection Controller [LADRC]. The field oriented control of IM needs the accuratemathematical model of IM, but it is very difficult to develop an accurate mathematical model. The LADRC does depend on the mathematical model so it is very robust to changes in plant parameters. This controller can also estimate and compensate the general disturbances which include the unknown internal dynamics and external disturbances by using the Extended State Observer, which can reduce the system to a linear one.
Chartering Launchers for Small Satellites
Hernandez, Daniel
The question of how to launch small satellites has been solved over the years by the larger launchers offering small satellites the possibility of piggy-backing. Specific fixtures have been developed and commercialized: Arianespace developed the ASAP interface, the USAF studied ESPA, NASA has promoted Shuttle launch possibilities, Russian authorities and companies have been able to find solutions with many different launchers... It is fair to say that most launcher suppliers have worked hard and finally often been able to find solutions to launch most small satellites into orbit. It is also true, however, that most of these small satellites were technology demonstration missions capable of accepting a wide range of orbit and launch characteristics: orbit altitude and inclination, launch date, etc. In some cases the small satellite missions required a well-defined type of orbit and have therefore been obliged to hire a small launcher on which they were the prime passenger. In our paper we would like to propose an additional solution to all these possibilities: launchers could plan well in advance (for example about 3 years), trips to precisely defined orbits to allow potential passengers to organize themselves and be ready on the D-Day. On the scheduled date the chartered launcher goes to the stated orbit while on another date, another chartered launcher goes to another orbit. The idea is to organize departures for space like trains or airplanes leaving on known schedules for known destinations.
Air-Cored Linear Induction Motor for Earth-to-Orbit Systems
Zabar, Zivan; Levi, Enrico; Birenbaum, Leo
1996-01-01
The need for lowering the cost of Earth-to-Orbit (ETO) launches has prompted consideration of electromagnetic launchers. A preliminary design based on the experience gained in an advanced type of coilgun and on innovative ideas shows that such a launcher is technically feasible with almost off-the-shelf components.
Bolonkin, Alexander
2009-01-01
A method and facilities for delivering payload and people into outer space are presented. This method uses, in general, engines located on a planetary surface. The installation consists of a space apparatus, power drive stations, which include a flywheel accumulator (for storage) of energy, a variable reducer, a powerful homopolar electric generator and electric rails. The drive stations accelerate the apparatus up to hypersonic speed. The estimations and computations show the possibility of making this project a reality in a short period of time (for payloads which can tolerate high g-forces). The launch will be very cheap at a projected cost of 3 - 5 dollars per pound. The authors developed a theory of this type of the launcher.
H3O+ tetrahedron induction in large negative linear compressibility
Wang, Hui; Feng, Min; Wang, Yu-Fang; Gu, Zhi-Yuan
2016-01-01
Despite the rarity, large negative linear compressibility (NLC) was observed in metal-organic framework material Zn(HO3PC4H8PO3H)∙2H2O (ZAG-4) in experiment. We find a unique NLC mechanism in ZAG-4 based on first-principle calculations. The key component to realize its large NLC is the deformation of H3O+ tetrahedron. With pressure increase, the oxygen apex approaches and then is inserted into the tetrahedron base (hydrogen triangle). The tetrahedron base subsequently expands, which results in the b axis expansion. After that, the oxygen apex penetrates the tetrahedron base and the b axis contracts. The negative and positive linear compressibility is well reproduced by the hexagonal model and ZAG-4 is the first MOFs evolving from non re-entrant to re-entrant hexagon framework with pressure increase. This gives a new approach to explore and design NLC materials. PMID:27184726
H3O(+) tetrahedron induction in large negative linear compressibility.
Wang, Hui; Feng, Min; Wang, Yu-Fang; Gu, Zhi-Yuan
2016-05-17
Despite the rarity, large negative linear compressibility (NLC) was observed in metal-organic framework material Zn(HO3PC4H8PO3H)∙2H2O (ZAG-4) in experiment. We find a unique NLC mechanism in ZAG-4 based on first-principle calculations. The key component to realize its large NLC is the deformation of H3O(+) tetrahedron. With pressure increase, the oxygen apex approaches and then is inserted into the tetrahedron base (hydrogen triangle). The tetrahedron base subsequently expands, which results in the b axis expansion. After that, the oxygen apex penetrates the tetrahedron base and the b axis contracts. The negative and positive linear compressibility is well reproduced by the hexagonal model and ZAG-4 is the first MOFs evolving from non re-entrant to re-entrant hexagon framework with pressure increase. This gives a new approach to explore and design NLC materials.
An axisymmetrical non-linear finite element model for induction heating in injection molding tools
Guerrier, Patrick; Nielsen, Kaspar Kirstein; Menotti, Stefano;
2016-01-01
To analyze the heating and cooling phase of an induction heated injection molding tool accurately, the temperature dependent magnetic properties, namely the non-linear B-H curves, need to be accounted for in an induction heating simulation. Hence, a finite element model has been developed...... in to the injection molding tool. The model shows very good agreement with the experimental temperature measurements. It is also shown that the non-linearity can be used without the temperature dependency in some cases, and a proposed method is presented of how to estimate an effective linear permeability to use...
Design and Analysis of Steerable ECRH Launcher for SST-1 Tokamak
Mistry, Hardik; Shukla, B. K.
2017-07-01
In the tokamaks ECRH system is used for pre-ionization, start up, heating, current drive and suppression of NTMs (Neo Classical Tearing Modes). A Standard ECRH system consists of high power microwave source Gyrotron, circular corrugated waveguide based transmission line and launcher. The Focused ECH power is launched into plasma through launcher. The microwave beam emerges out from circular corrugated waveguide and propagates freely in air with finite divergence. So focusing and plane mirror combination is used to launch focused beam in plasma. Thus an ECRH launcher consists of metallic profiled and plane mirror, UHV compatible vacuum barrier window and a UHV gate valve. One 42 GHz gyrotron capable of delivering 500 kW of power for 500 ms and other 82 GHz gyrotron capable of delivering 200 kW of power for 1000s are used for SST-1 ECRH system. The launcher design consists of mirror design, design of supports and design of steering mechanism to provide suitable movements with minimum backless error. The whole assembly is UHV compatible. The launcher is capable of steering the beams by ±20° in both toroidal and poloidal directions. Mirrors are given motion by means of one rotary and one linear feedthrough. For 82 GHz launcher active cooling is provided, whereas for 42 GHz launcher no active cooling is provided. A detailed analysis is carried out for the mirrors of the high power launcher. The heat load for the 82 GHz launcher is 2 kW ( 1% absorption) and for 42 GHz launcher it is 5 kW. For 82 GHz launcher, the maximum steady state surface temperatures of focusing and reflecting mirrors are 315K and 323K and von-mises stresses are within 10 MPa. Similarly for 42 GHz launcher maximum temperatures observed during 500 ms pulse are 301K and 303K for focusing and reflecting mirrors respectively. This paper explains the mechanical and thermal design and analysis of the launcher for the ECRH system.
Inductively commutated coilguns
Mongeau, P.P. (EML Research, Inc., Hudson, MA (US))
1991-01-01
In this paper the concept and relevance of power factor is presented in regards to high performance launchers. As the scale of launchers grows and as efforts to improve efficiency continue power factor considerations will become crucial in engineering design and ultimate launcher performance limits. The use of motion induced commutation to improve the power factor are discussed. Various approaches to inductive commutation are presented, including: the brush-commutated 9 MJ Coilgun, the solid state-switched coilgun and the quenchgun.
Inductively commutated coilguns
Mongeau, Peter P.
1991-01-01
The concept and relevance of power factor is presented in the context of high-performance launchers. As the scale of launchers grows and efforts to improve efficiency continue, power factor considerations will become crucial in engineering design and ultimate launcher performance limits. The use of motion-induced commutation to improve the power factor are discussed. Various approaches to inductive commutation are presented, including the brush-commutated 9-MJ coilgun, the solid state-switched coilgun, and the quenchgun.
Design of a small Annular Linear Induction Electromagnetic Pump - Simulation and Experiment
Yong-Lin, Ma; Yan-Jiang, Chen; Tao, Jiang; Shu-Qing, Xing
2015-01-01
International audience; An annular linear induction electromagnetic pump (ALIP) is used for pumping liquid tin alloy with a flow rate and developed pressure of 17l /min and 0.5bar respectively. The electromagnetic force, flux density and inducted current density are calculated using a by finite element method (FEM) the various design variables. The performance of ALIP is tested with liquid tin for various melting point temperatures. Results show that pressure increases as electromagnetic forc...
M. S. MANNA
2011-12-01
Full Text Available The development of electromagnetic devices as machines, transformers, heating devices confronts the engineers with several problems. For the design of an optimized geometry and the prediction of the operational behaviour an accurate knowledge of the dependencies of the field quantities inside the magnetic circuits is necessary. This paper provides the eddy current and core flux density distribution analysis in linear induction motor. Magnetic flux in the air gap of the Linear Induction Motor (LIM is reduced to various losses such as end effects, fringes, effect, skin effects etc. The finite element based software package COMSOL Multiphysics Inc. USA is used to get the reliable and accurate computational results for optimization the performance of Linear Induction Motor (LIM. The geometrical characteristics of LIM are varied to find the optimal point of thrust and minimum flux leakage during static and dynamic conditions.
A speed estimation unit for induction motors based on adaptive linear combiner
Marei, Mostafa I.; Shaaban, Mostafa F.; El-Sattar, Ahmed A. [Department of Electrical Power and Machines, Faculty of Engineering, Ain Shams University, Cairo 11517 (Egypt)
2009-07-15
This paper presents a new induction motor speed estimation technique, which can estimate the rotor resistance as well, from the measured voltage and current signals. Moreover, the paper utilizes a novel adaptive linear combiner (ADALINE) structure for speed and rotor resistance estimations. This structure can deal with the multi-output systems and it is called MO-ADALINE. The model of the induction motor is arranged in a linear form, in the stationary reference frame, to cope with the proposed speed estimator. There are many advantages of the proposed unit such as wide speed range capability, immunity against harmonics of measured waveforms, and precise estimation of the speed and the rotor resistance at different dynamic changes. Different types of induction motor drive systems are used to evaluate the dynamic performance and to examine the accuracy of the proposed unit for speed and rotor resistance estimation. (author)
THE STUDY OF SELF-BALANCED POTATO SORTING MACHINE WITH LINEAR INDUCTION DRIVE
Linenko A. V.
2016-04-01
Full Text Available In the article we have considered the self-balanced potato sorting machine differing from existing designs of self-balanced potato sorting machines with an oscillatory electric drive. That drive uses a linear induction motor. As the counterbalancing device, the method of the duplicating mechanism is applied. The duplicating mechanism is a specular reflection of the main working body, and also participates in technological process. Its application in the drive of machine allows not only to increase efficiency of cleaning, drying and sorting of potatoes, but also to increase reliability of sorting installation that corresponds to the newest tendencies of development of technology. We have brought the mathematical model of the offered electric drive of potato sorting machine, which is implemented in the environment of object and visual modeling of Matlab |Simulink|. The mathematical model allows investigating influence of parameters of the linear induction electric drive on parameters of oscillatory process of working body in dynamics. The developed technique of research and the created experimental potato sorting machine with the linear induction drive have confirmed theoretical researches. The main kinematic sizes of machine and technical parameters of individual nodes are determined. It is shown, that the efficiency of inertial transportation can be increased for 20% in comparison with the classical drive from the motor of rotation. Results of research will allow to realize energetically and technologically effective potato sorting machines with the linear induction drive
Mathematical Model of Linear Switched Reluctance Motor with Mutual Inductance Consideration
Nikolay Grebennikov
2015-06-01
Full Text Available This paper presents developing an mathematical model for linear switched reluctance motor (LSRM with account of the mutual inductance between the phases. Mutual interaction between the phases of LSRM gives the positive effect, as a rule the power of the machine is increased by 5-15%.
MULTIPLE ECH LAUNCHER CONTROL SYSTEM
GREEN,M.T; PONCE,D; GRUNLOH,H.J; ELLIS,R.A; GROSNICKLE,W.H; HUMPHREY,R.L
2003-10-01
OAK-B135 The addition of new, high power gyrotrons to the heating and current drive arsenal at DIII-D, required a system upgrade for control of fully steerable ECH Launchers. Each launcher contains two pointing mirrors with two degrees of mechanical freedom. The two flavors of motion are called facet and tilt. Therefore up to four channels of motion per launcher need to be controlled. The system utilizes absolute encoders to indicate mirror position and therefore direction of the microwave beam. The launcher movement is primarily controlled by PLC, but future iterations of design, may require this control to be accomplished by a CPU on fast bus such as Compact PCI. This will be necessary to accomplish real time position control. Safety of equipment and personnel is of primary importance when controlling a system of moving parts. Therefore multiple interlocks and fault status enunciators have been implemented. This paper addresses the design of a Multiple ECH Launcher Control System, and characterizes the flexibility needed to upgrade to a real time position control system in the future.
Modeling and Simulating of Single Side Short Stator Linear Induction Motor with the End Effect
Hamzehbahmani, Hamed
2011-09-01
Linear induction motors are under development for a variety of demanding applications including high speed ground transportation and specific industrial applications. These applications require machines that can produce large forces, operate at high speeds, and can be controlled precisely to meet performance requirements. The design and implementation of these systems require fast and accurate techniques for performing system simulation and control system design. In this paper, a mathematical model for a single side short stator linear induction motor with a consideration of the end effects is presented; and to study the dynamic performance of this linear motor, MATLAB/SIMULINK based simulations are carried out, and finally, the experimental results are compared to simulation results.
Space transportation propulsion USSR launcher technology, 1990
1991-01-01
Space transportation propulsion U.S.S.R. launcher technology is discussed. The following subject areas are covered: Energia background (launch vehicle summary, Soviet launcher family) and Energia propulsion characteristics (booster propulsion, core propulsion, and growth capability).
Mosallanejad, Ali; Shoulaie, Abbas
2011-07-01
This paper reports a study of coil inductance profile in all positions of plunger in tubular linear reluctance motors (TLRMs) with open type magnetic circuits. In this paper, maximum inductance calculation methods in winding of tubular linear reluctance motors are described based on energy method. Furthermore, in order to calculate the maximum inductance, equivalent permeability is measured. Electromagnetic finite-element analysis for simulation and calculation of coil inductance in this motor is used. Simulation results of coil inductance calculation using 3-D FEM with coil current excitation is compared to theoretical and experimental results. The comparison yields a good agreement.
Generic Software Architecture for Launchers
Carre, Emilien; Gast, Philippe; Hiron, Emmanuel; Leblanc, Alain; Lesens, David; Mescam, Emmanuelle; Moro, Pierre
2015-09-01
The definition and reuse of generic software architecture for launchers is not so usual for several reasons: the number of European launcher families is very small (Ariane 5 and Vega for these last decades); the real time constraints (reactivity and determinism needs) are very hard; low levels of versatility are required (implying often an ad hoc development of the launcher mission). In comparison, satellites are often built on a generic platform made up of reusable hardware building blocks (processors, star-trackers, gyroscopes, etc.) and reusable software building blocks (middleware, TM/TC, On Board Control Procedure, etc.). If some of these reasons are still valid (e.g. the limited number of development), the increase of the available CPU power makes today an approach based on a generic time triggered middleware (ensuring the full determinism of the system) and a centralised mission and vehicle management (offering more flexibility in the design and facilitating the long term maintenance) achievable. This paper presents an example of generic software architecture which could be envisaged for future launchers, based on the previously described principles and supported by model driven engineering and automatic code generation.
Combined Sliding Mode Control with a Feedback Linearization for Speed Control of Induction Motor
Aamir Hashim Obeid Ahmed
2011-06-01
Full Text Available Induction Motor (IM speed control is an area of research that has been in prominence for some time now. In this paper, a nonlinear controller is presented for IM drives. The nonlinear controller is designed based on input-output feedback linearization control technique, combined with sliding mode control (SMC to obtain a robust, fast and precise control of IM speed. The input-output feedback linearization control decouples the flux control from the speed control and makes the synthesis of linear controllers possible. To validate the performances of the proposed control scheme, we provided a series of simulation results and a comparative study between the performances of the proposed control strategy and those of the feedback linearization control (FLC schemes. Simulation results show that the proposed control strategy scheme shows better performance than the FLC strategy in the face of system parameters variation
Peresada, Sergei; Kovbasa, Serhii; Dymko, Serhii; BOZHKO, Serhiy
2016-01-01
The paper presents a novel maximum torque per Ampere (MTA) controller for induction motor (IM) drives. The proposed controller exploits the concept of direct (observer based) field orientation and guarantees asymptotic torque tracking of smooth reference trajectories and maximizes the torque per Ampere ratio when the developed torque is constant or slowly varying. A dynamic output-feedback linearizing technique is employed for the torque subsystem design. In order to improve torque tracking a...
Nondahl, T. A.; Richter, E.
1980-09-01
A design study of two types of single sided (with a passive rail) linear electric machine designs, namely homopolar linear synchronous machines (LSM's) and linear induction machines (LIM's), is described. It is assumed the machines provide tractive effort for several types of light rail vehicles and locomotives. These vehicles are wheel supported and require tractive powers ranging from 200 kW to 3735 kW and top speeds ranging from 112 km/hr to 400 km/hr. All designs are made according to specified magnetic and thermal criteria. The LSM advantages are a higher power factor, much greater restoring forces for track misalignments, and less track heating. The LIM advantages are no need to synchronize the excitation frequency precisely to vehicle speed, simpler machine construction, and a more easily anchored track structure. The relative weights of the two machine types vary with excitation frequency and speed; low frequencies and low speeds favor the LSM.
Electromagnetic launchers for space applications
Schroeder, J. M.; Gully, J. H.; Driga, M. D.
1989-01-01
An electromagnetic launcher (EML) was designed for NASA-Langley to boost large models to hypervelocity for flight evaluation. Two different concepts were developed using railgun and coilgun principles. A coilgun was designed to accelerate a 14-kg mass to 6 km/s and, by adding additional equipment, to accelerate a 10-kg mass to 11 km/s. The railgun system was designed to accelerate only 14 kg to 6 km/s. Of significance in this development is the opportunity to use the launcher for aeroballistic research of the upper atmosphere, eventually placing packages in low earth orbit using a small rocket. The authors describe the railgun and coilgun launch designs and suggest a reconfiguration for placement of 150-kg parcels into low earth orbit for aeroballistic studies and possible space lab support. Each design is detailed along with the performance adjustments which would be required for circular orbit payload placement.
Advanced Model of Electromagnetic Launcher
Karel Leubner
2015-01-01
Full Text Available An advanced 2D model of electromagnetic launcher is presented respecting the influence of eddy currents induced in the accelerated ferromagnetic body. The time evolution of electromagnetic field in the system, corresponding forces acting on the projectile and time evolutions of its velocity and current in the field circuit are solved numerically using own application Agros2d. The results are then processed and evaluated in Wolfram Mathematica. The methodology is illustrated with an example whose results are discussed.
Roussy, Georges; Kongmark, Nils
2003-01-01
It is shown that a bi-directional waveguide launcher can be used advantageously for reducing the reflection coefficient mismatch of an input impedance of an applicator. In a simple bi-directional waveguide launcher, the magnetron is placed in the waveguide and generates a nominal field distribution with significant output impedance in both directions of the waveguide. If a standing wave is tolerated in the torus, which connects the launcher and the applicator, the power transfer from the magnetron to the applicator can be optimal, without using special matching devices. It is also possible to match the bi-directional launcher with two inductance stubs near the antenna of the magnetron and use them for supplying a two-input applicator without reflection.
Single neuron network PI control of high reliability linear induction motor for Maglev
FANG You-tong; FAN Cheng-zhi
2007-01-01
The paper deals with a new model of linear induction motor (LIM) to improve the reliability of the system. Based on the normal equation circuit of LIM considering the dynamic end effect, an equivalent circuit model with compensation of large end effect is constructed when the end effect force at synchronism is of braking character. The equivalent circuit model is used for secondary-flux oriented control of LIM. Single neuron network PI unit for LIM servo-drive is also discussed. The effectiveness of mathematical model for drive control is verified by simulations.
Linearization Method for Starting Control of Speed-Sensorless Vector-Controlled Induction Motors
Fujinami, Kazuki; Kondo, Keiichiro
A linearization method is proposed for controlling the start-up operation of a rotating induction motor. The dynamics of this motor are deteriorated when the starting operation is carried out at high frequencies. In this method, the characteristics of the method are analyzed to reveal that the aforementioned problem is caused by the low equivalent gain of the induced voltage during the rotor flux establishment. A method to compensate for the angle of the rotor-flux-induced voltage vector is proposed to overcome this problem. The proposed method is experimentally verified by a test set, and the influence of changes in the rotor resistance is analyzed.
Application of an imperialist competitive algorithm to the design of a linear induction motor
Lucas, Caro [Center of Excellence, Control and Intelligent Processing, School of Electrical and Computer Engineering, University of Tehran, Tehran 4563-11155 (Iran, Islamic Republic of); Nasiri-Gheidari, Zahra, E-mail: z_nasiri_gh@yahoo.co [School of Electrical and Computer Eng., University of Tehran, Tehran 4563-11155 (Iran, Islamic Republic of); Tootoonchian, Farid [Department of Electrical Engineering, Iran University of Science and Technology, Tehran 16846-13114 (Iran, Islamic Republic of)
2010-07-15
In this paper a novel optimization algorithm based on imperialist competitive algorithm (ICA) is used for the design of a low speed single sided linear induction motor (LIM). This type of motors is used increasingly in industrial process specially in transportation systems. In these applications having high efficiency with high power factor is very important. So in this paper the objective function of design is presented considering both efficiency and power factor. Finally the results of ICA are compared with the ones of genetic algorithm and conventional design. Comparison shows the success of ICA for design of LIMs.
Design of a Linear Induction 1-MV Injector for the Relativisitic Two-Beam Accelerator
Anderson, D. E.; Henestroza, E.; Houck, T.; Lidia, S.; Reginato, L.; Vanecek, D.; Westenskow, G.; Yu, S.
1997-05-01
A Relativisitic Klystron Two-Beam Accelerator (RTA) is envisioned as a RF power source upgrade of the Next Linear Collider. A prototype to study physics, engineering and costing issues is presently under construction at Lawrence Berkeley National Laboratory. The first half of the injector, a 1 MeV, 1.2 kA, 300 ns induction electron gun, has been built and is presently being tested. The design of the injector cells and pulsed power drive units will be presented. Preliminary test results of the power drive units will also be given.
Prasenjit D. Wakode
2016-07-01
Full Text Available This paper presents the complete analysis of Linear Induction Motor (LIM under VVVF. The complete variation of LIM air gap flux under ‘blocked Linor’ condition and starting force is analyzed and presented when LIM is given VVVF supply. The analysis of this data is important in further understanding of the equivalent circuit parameters of LIM and to study the magnetic circuit of LIM. The variation of these parameters is important to know the LIM response at different frequencies. The simulation and application of different control strategies such as vector control thus becomes quite easy to apply and understand motor’s response under such strategy of control.
Particle Swarm Based Approach of a Real-Time Discrete Neural Identifier for Linear Induction Motors
Alma Y. Alanis
2013-01-01
Full Text Available This paper focusses on a discrete-time neural identifier applied to a linear induction motor (LIM model, whose model is assumed to be unknown. This neural identifier is robust in presence of external and internal uncertainties. The proposed scheme is based on a discrete-time recurrent high-order neural network (RHONN trained with a novel algorithm based on extended Kalman filter (EKF and particle swarm optimization (PSO, using an online series-parallel con figuration. Real-time results are included in order to illustrate the applicability of the proposed scheme.
A 10-stage reconnection demonstration launcher
Cnare, E.C.; Widner, M.M.; Duggin, B.W.
1989-01-01
A small-scale, 10-stage cylindrical reconnection launcher has been designed, fabricated, and tested. Ten-gram projectiles are accelerated from rest to 317 m/s through the 0.44 m launcher assembly with a projectile kinetic energy to capacitor stored energy efficiency of 9%. Comparison of test results and computer code predictions will be presented. Results of these studies have substantiated launcher scaling at small size and have provided a useful test bed for launcher components and diagnostics. 5 refs., 6 figs.
Induction Motor Drive System Based on Linear Active Disturbance Rejection Controller
Liu, Liying; Zhang, Yongli; Yao, Qingmei
It is difficult to establish an exact mathematical model for the induction motor and the robustness is poor of the vector control system using PI regulator. This paper adopts the linear active disturbance rejection controller (LADRC) to control inductor motor. LADRC doesn't need the exact mathematical model of motor and it can not only estimate but also compensate the general disturbance that includes the coupling items in model of motor and parameters perturbations by linear extended state observer (LESO), so the rotor flux and torque fully decouple. As a result, the performance is improved. To prove the above control scheme, the proposed control system has been simulated in MATLAB/SIMULINK, and the comparison was made with PID. Simulation results show that LADRC' has better performance and robustness than PID.
The pulsed linear induction motor concept for high-speed trains
Turman, B.N.; Marder, B.M.; Rohwein, G.J.; Aeschliman, D.P.; Kelley, J.B.; Cowan, M.; Zimmerman, R.M.
1995-06-01
The SERAPBIM (SEgmented RAil PHased Induction Motor) concept is a linear induction motor concept which uses rapidly-pulsed magnetic fields and a segmented reaction rail, as opposed to low-frequency fields and continuous reaction rails found in conventional linear induction motors. These improvements give a high-traction, compact, and efficient linear motor that has potential for advanced high speed rail propulsion. In the SERAPBIM concept, coils on the vehicle push against a segmented aluminum rail, which is mounted on the road bed. Current is pulsed as the coils cross an edge of the segmented rail, inducing surface currents which repel the coil. The coils must be pulsed in synchronization with the movement by reaction rail segments. This is provided by a sense-and-fire circuit that controls the pulsing of the power modulators. Experiments were conducted to demonstrate the feasibility of the pulsed induction motor and to collect data that could be used for scaling calculations. A 14.4 kg aluminum plate was accelerated down a 4 m track to speeds of over 15 m/sec with peak thrust up to 18 kN per coilset. For a trainset capable of 200 mph speed, the SERAPHIM concept design is based on coils which are each capable of producing up to 3.5 kN thrust, and 30 coil pairs are mounted on each power car. Two power cars, one at each end of the train, provide 6 MW from two gas turbine prime power units. The thrust is about 210.000 N and is essentially constant up to 200 km/hr since wheel slippage does not limit thrust as with conventional wheeled propulsion. A key component of the SERAPHIM concept is the use of passive wheel-on-rah support for the high speed vehicle. Standard steel wheels are capable of handling over 200 mph. The SERAPHIM cost is comparable to that for steel-wheel high-speed rail, and about 10% to 25% of the projected costs for a comparable Maglev system.
Khaled N. Faris
2015-12-01
Full Text Available According to various advantages of linear induction motor (LIM, such as high starting thrust force, high speed operation and reduction of mechanical losses, more applications have utilized this type of motors. Direct Thrust Control (DTC technique is considered as one of the most efficient techniques that can be used for LIM. DTC is preferable to give a fast and good dynamic thrust response. So, to improve the accuracy and robustness of contouring control for CNC machine tools, linear induction motors with a direct thrust control technique are introduced for driving these machines. An industry standard motion control system is applied for reducing the tracking error and improving the desired accuracy. Different loading conditions are simulated to validate the reliability and robustness of the introduced system to match the application field. The proposed system is simulated using the MATLAB/SIMULINK Package; simulation results validated both tracking accuracy and robustness of the proposed motion control system for contouring control for a CNC (Computer Numerical Control milling machine.
Zhao, J.; Zheng, T. Q.; Zhang, W.; Fang, J.; Liu, Y. M.
2011-11-01
A new type high temperature superconductor linear induction motor is designed and analyzed as a prototype to ensure applicability aimed at industrial motors. Made of Bi-2223/Ag, primary windings are distributed with the double-layer concentrated structure. The motor is analyzed by 2D electromagnetic Finite Element Method to get magnetic field distribution, thrust force, vertical force and so on. The critical current of motor and the electromagnetic force are mostly decided by the leakage flux density of primary slot and by the main magnetic flux and eddy current respectively. The structural parameters of motor have a great influence on the distribution of magnetic field. Under constant currents, the properties of motor are analyzed with different slot widths, slot heights and winding turns. The properties of motor, such as the maximum slot leakage flux density, motor thrust and motor vertical force, are analyzed with different structural parameters.
Adaptive Command-Filtered Backstepping Control for Linear Induction Motor via Projection Algorithm
Wenxu Yan
2016-01-01
Full Text Available A theoretical framework of the position control for linear induction motors (LIM has been proposed. First, indirect field-oriented control of LIM is described. Then, the backstepping approach is used to ensure the convergence and robustness of the proposed control scheme against the external time-varying disturbances via Lyapunov stability theory. At the same time, in order to solve the differential expansion and the control saturation problems in the traditional backstepping, command filter is designed in the control and compensating signals are presented to eliminate the influence of the errors caused by command filters. Next, unknown total mass of the mover, viscous friction, and load disturbances are estimated by the projection-based adaptive law which bounds the estimated function and simultaneously guarantees the robustness of the proposed controller against the parameter uncertainties. Finally, simulation results are given to illustrate the validity and potential of the designed control scheme.
Bousserhane I.K.
2006-01-01
Full Text Available In this paper the position control of a linear induction motor using adaptive fuzzy back stepping design with integral action is proposed. First, the indirect field oriented control for LIM is derived. Then, an integral back stepping design for indirect field oriented control of LIM is proposed to compensate the uncertainties which occur in the control. Finally, the fuzzy integral-back stepping controller is investigated, where a simple fuzzy inference mechanism is used to achieve a position tracking objective under the mechanical parameters uncertainties. The effectiveness of the proposed control scheme is verified by numerical simulation. The numerical validation results of the proposed scheme have presented good performances compared to the conventional integral back stepping control.
Shurter, R.P.; Moir, D.C.; Devlin, D.J.; Springer, R.W.
1997-08-01
Investigations are underway at Los Alamos to develop a new generation of high current, low source temperature photo cathodes able to operate in vacuum environments with pressures above 10e-6 torr without poisoning or degradation of emission properties. Polycrystalline diamond films are emerging as the ideal material for these photocathodes. Robustness, high quantum efficiency and high thermal conductivity are fundamental necessary attributes that are found in diamond. The high electron/hole mobility in the boron doped diamond lattice and the ability to create a negative electron affinity surface through downward band bending allow for high current density emission with quantum efficiencies of 0.5% when illuminated by a ArF laser. We report the results to date toward the development of a four kiloampere photocathode with a source temperature below 5eV for the DARHT linear induction Accelerator
Kilbane, J.; Polzin, K. A.
2014-01-01
An annular linear induction pump (ALIP) that could be used for circulating liquid-metal coolant in a fission surface power reactor system is modeled in the present work using the computational COMSOL Multiphysics package. The pump is modeled using a two-dimensional, axisymmetric geometry and solved under conditions similar to those used during experimental pump testing. Real, nonlinear, temperature-dependent material properties can be incorporated into the model for both the electrically-conducting working fluid in the pump (NaK-78) and structural components of the pump. The intricate three-phase coil configuration of the pump is implemented in the model to produce an axially-traveling magnetic wave that is qualitatively similar to the measured magnetic wave. The model qualitatively captures the expected feature of a peak in efficiency as a function of flow rate.
Electromagnetic Performance Calculation of HTS Linear Induction Motor for Rail Systems
Liu, Bin; Fang, Jin; Cao, Junci; Chen, Jie; Shu, Hang; Sheng, Long
2017-07-01
According to a high temperature superconducting (HTS) linear induction motor (LIM) designed for rail systems, the influence of electromagnetic parameters and mechanical structure parameters on the electromagnetic horizontal thrust, vertical force of HTS LIM and the maximum vertical magnetic field of HTS windings are analyzed. Through the research on the vertical field of HTS windings, the development regularity of the HTS LIM maximum input current with different stator frequency and different thickness value of the secondary conductive plate is obtained. The theoretical results are of great significance to analyze the stability of HTS LIM. Finally, based on theory analysis, HTS LIM test platform was built and the experiment was carried out with load. The experimental results show that the theoretical analysis is correct and reasonable.
Analysis and measure of novel stereo-garage driven by linear induction motor
Lu Qinfen
2015-12-01
Full Text Available The car access time is a key parameter, especially in a huge stereo-garage, where this one should be decreased as much as possible. This paper proposes a novel stereo-garage. Adopting the linear induction motors (LIMs, the system has a simple structure and rapid response capability. In the stereo-garage, several LIMs are installed below the crossbeam on a lifting platform, and several LIMs are fixed on the top of a moving frame. During the operation of LIMs, the moving frame moves forward and backward to reach the required parking place, whereas the crossbeam moves horizontally in order to take or store the vehicle rapidly. All these LIMs are the same and should be designed at a low frequency. The influences of key structure parameters and dynamic performances are investigated, based on FEM. The predicted results are validated by a prototype. Finally, the designed LIMs are successfully applied in two 8-layer stereo-garages.
Rail Brake System Using a Linear Induction Motor for Dynamic Braking
Sakamoto, Yasuaki; Kashiwagi, Takayuki; Tanaka, Minoru; Hasegawa, Hitoshi; Sasakawa, Takashi; Fujii, Nobuo
One type of braking system for railway vehicles is the eddy current brake. Because this type of brake has the problem of rail heating, it has not been used for practical applications in Japan. Therefore, we proposed the use of a linear induction motor (LIM) for dynamic braking in eddy current brake systems. The LIM reduces rail heating and uses an inverter for self excitation. In this paper, we estimated the performance of an LIM from experimental results of a fundamental test machine and confirmed that the LIM generates an approximately constant braking force under constant current excitation. At relatively low frequencies, this braking force remains unaffected by frequency changes. The reduction ratio of rail heating is also approximately proportional to the frequency. We also confirmed that dynamic braking resulting in no electrical output can be used for drive control of the LIM. These characteristics are convenient for the realization of the LIM rail brake system.
Yamamoto, Shu; Yamaguchi, Tomonobu; Hirahara, Hideaki; Ara, Takahiro
This paper presents asymmetric circuit models and an inductance parameter measurement method for Permanent Magnet Linear Synchronous Motors (PMLSMs). The reason why the tested PMLSM with surface permanent magnet structure exhibits both asymmetry and salient pole natures is investigated. Asymmetric circuit models considering the saliency and inductance harmonic effects are discussed for PMLSM fed by three-phase three-wire power source systems. All fundamental and harmonic inductance parameters are easily determined by a standstill test using a single-phase commercial source. Experimental and simulation results on a single-sided PMLSM with a 3-phase, 4-pole and 14-slot mover demonstrate the validity of the proposed method.
Fuzzy virtual reference model sensorless tracking control for linear induction motors.
Hung, Cheng-Yao; Liu, Peter; Lian, Kuang-Yow
2013-06-01
This paper introduces a fuzzy virtual reference model (FVRM) synthesis method for linear induction motor (LIM) speed sensorless tracking control. First, we represent the LIM as a Takagi-Sugeno fuzzy model. Second, we estimate the immeasurable mover speed and secondary flux by a fuzzy observer. Third, to convert the speed tracking control into a stabilization problem, we define the internal desired states for state tracking via an FVRM. Finally, by solving a set of linear matrix inequalities (LMIs), we obtain the observer gains and the control gains where exponential convergence is guaranteed. The contributions of the approach in this paper are threefold: 1) simplified approach--speed tracking problem converted into stabilization problem; 2) omit need of actual reference model--FVRM generates internal desired states; and 3) unification of controller and observer design--control objectives are formulated into an LMI problem where powerful numerical toolboxes solve controller and observer gains. Finally, experiments are carried out to verify the theoretical results and show satisfactory performance both in transient response and robustness.
Study of new materials for railgun launchers
Poltanov, A.; Jygailo, N.; Bykov, M.; Glinov, A. [Troitsk Inst. for Innovations and Fusion Research (Russian Federation); Svobodov, A. [State Scientific Technology Center TEMP, Moscow (Russian Federation); Belyakov, A.; Chernetskaya, N. [Mendeleev Univ. of Chemical Technology of Russia, Moscow (Russian Federation)
1997-01-01
The description of new materials which can be used in railgun launchers is presented. Mo-W compositions in the Cu matrix, binary composites with anisotropic conductivity, ceramics and ceramic covers have been studied as materials for rails, solid armature and insulator respectively. The tests have been conducted on a 1m long railgun launcher with a section of the bore 10mm x 10mm using a current with the amplitude 350--400 kA. Main test results are demonstrated.
Results from Sandia National Laboratories/Lockheed Martin Electromagnetic Missile Launcher (EMML).
Lockner, Thomas Ramsbeck; Skurdal, Ben (Lockheed Martin MS2, Baltimore, MD); Gaigler, Randy (Lockheed Martin MS2, Baltimore, MD); Basak, L (Lockheed Martin MS2, Baltimore, MD); Root, G (Lockheed Martin MS2, Baltimore, MD); Aubuchon, Matthew S.; Turman, Bobby N.; Floyd, Mendel D. (Lockheed Martin MS2, Baltimore, MD)
2005-05-01
Sandia national laboratories (SNL) and lockheed martin MS2 are designing an electromagnetic missile launcher (EMML) for naval applications. The EMML uses an induction coilgun topology with the requirement of launching a 3600 lb. missile up to a velocity of 40 m/s. To demonstrate the feasibility of the electromagnetic propulsion design, a demonstrator launcher was built that consists of approximately 10% of the propulsion coils needed for a tactical design. The demonstrator verified the design by launching a 1430 lb weighted sled to a height of 24 ft in mid-December 2004 (Figure 1). This paper provides the general launcher design, specific pulsed power system component details, system operation, and demonstration results.
G.M. Golenkov
2014-03-01
Full Text Available The paper presents results of computer simulation and experimental study of magnetic induction distribution in a coaxial linear motor air gap throughout the length of the runner active part at different heights of the air gap between the runner and the inductor magnetic core for motors with axial and radial direction of the permanent magnets magnetization.
The Experimental Study of Rayleigh-Taylor Instability using a Linear Induction Motor Accelerator
Yamashita, Nicholas; Jacobs, Jeffrey
2009-11-01
The experiments to be presented utilize an incompressible system of two stratified miscible liquids of different densities that are accelerated in order to produce the Rayleigh-Taylor instability. Three liquid combinations are used: isopropyl alcohol with water, a calcium nitrate solution or a lithium polytungstate solution, giving Atwood numbers of 0.11, 0.22 and 0.57, respectively. The acceleration required to drive the instability is produced by two high-speed linear induction motors mounted to an 8 m tall drop tower. The motors are mounted in parallel and have an effective acceleration length of 1.7 m and are each capable of producing 15 kN of thrust. The liquid system is contained within a square acrylic tank with inside dimensions 76 x76x184 mm. The tank is mounted to an aluminum plate, which is driven by the motors to create constant accelerations in the range of 1-20 g's, though the potential exists for higher accelerations. Also attached to the plate are a high-speed camera and an LED backlight to provide continuous video of the instability. In addition, an accelerometer is used to provide acceleration measurements during each experiment. Experimental image sequences will be presented which show the development of a random three-dimensional instability from an unforced initial perturbation. Measurements of the mixing zone width will be compared with traditional growth models.
Fang, J.; Sheng, L.; Li, D.; Zhao, J.; Li, Sh.; Qin, W.; Fan, Y.; Zheng, Q. L.; Zhang, W.
A novel High Temperature Superconductor Linear Induction Motor (HTS LIM) is researched in this paper. Since the critical current and the electromagnetic force of the motor are determined mainly by the primary slot leakage flux, the main magnetic flux and eddy current respectively, in order to research the influence of structural parameters and operating parameters on electromagnetic properties of HTS LIM, the motor was analyzed by 2D transient Finite Element Method (FEM). The properties of the motor, such as the maximum slot leakage flux density, motor thrust, motor vertical force and critical current are analyzed with different structural parameters and operating parameters. In addition, an experimental investigation was carried out on prototype HTS motor. Electrical parameters were deduced from these tests and also compared with the analysis results from FEM. AC losses of one HTS coil in the motor were measured and AC losses of all HTS coils in HTS LIM were estimated. The results in this paper could provide reference for the design and research on the HTS LIM.
Monte Carlo simulations for 20 MV X-ray spectrum reconstruction of a linear induction accelerator
WANG Yi; LI Qin; JIANG Xiao-Guo
2012-01-01
To study the spectrum reconstruction of the 20 MV X-ray generated by the Dragon-I linear induction accelerator,the Monte Carlo method is applied to simulate the attenuations of the X-ray in the attenuators of different thicknesses and thus provide the transmission data.As is known,the spectrum estimation from transmission data is an ill-conditioned problem.The method based on iterative perturbations is employed to derive the X-ray spectra,where initial guesses are used to start the process.This algorithm takes into account not only the minimization of the differences between the measured and the calculated transmissions but also the smoothness feature of the spectrum function.In this work,various filter materials are put to use as the attenuator,and the condition for an accurate and robust solution of the X-ray spectrum calculation is demonstrated.The influences of the scattering photons within different intervals of emergence angle on the X-ray spectrum reconstruction are also analyzed.
Design of an Annular Linear Induction Pump for Nuclear Space Applications
Carloa O. Maidana; James E. Werner; Daniel M. Wachs
2011-02-01
Abstract. The United States Department of Energy's (DOE) Office of Nuclear Energy, Science, and Technology is supporting the National Aeronautics and Space Administration (NASA) in evaluating space mission power, propulsion systems and technologies to support the implementation of the Vision for Space Exploration (VSE). NASA will need increased power for propulsion and for surface power applications to support both robotic and human space exploration missions. As part of the Fission Surface Power Technology Project for the development of nuclear reactor technologies for multi-mission spacecrafts, an Annular Linear Induction Pump, a type of Electromagnetic Pump for liquid metals, able to operate in space has to be designed. Results of such design work are described as well as the fundamental ideas behind the development of an optimized design methodology. This project, which is a collaboration between Idaho National Laboratory (INL), Pacific Northwest National Laboratory (PNNL) and Marshall Space Flight Center (MSFC), involves the use of theoretical, computational and experimental tools for multi-physics analysis as well as advanced engineering design methods and techniques.
Performance Testing of a Prototypic Annular Linear Induction Pump for Fission Surface Power
Polzin, K. A.; Pearson, J. B.; Schoenfeld, M. P.; Webster, K.; Houts, M. G.; Godfroy, T. J.; Bossard, J. A.
2010-01-01
Results of performance testing of an annular linear induction pump are presented. The pump electromagnetically pumps liquid metal (NaK) through a circuit specially designed to allow for quantification of the performance. Testing was conducted over a range of conditions, including frequencies of 33, 36, 39, and 60 Hz, liquid metal temperatures from 25 to 525 C, and input voltages from 5 to 120 V. Pump performance spanned a range of flow rates from roughly 0.16 to 5.7 L/s (2.5 to 90 gpm), and pressure head <1 to 90 kPa (<0.145 to 13 psi). The maximum efficiency measured during testing was slightly greater than 6%. The efficiency was fairly insensitive to input frequency from 33 to 39 Hz, and was markedly lower at 60 Hz. In addition, the efficiency decreased as the NaK temperature was raised. While the pump was powered, the fluid responded immediately to changes in the input power level, but when power was removed altogether, there was a brief slow-down period before the fluid would come to rest. The performance of the pump operating on a variable frequency drive providing 60 Hz power compared favorably with the same pump operating on 60 Hz power drawn directly from the electrical grid.
Performance of an Annular Linear Induction Pump with Applications to Space Nuclear Power Systems
Polzin, Kurt A.; Schoenfeld, Michael; Pearson, J. Boise; Webster, Kenneth; Godfroy, Thomas; Adkins, Harold E., Jr.; Werner, James E.
2010-01-01
Results of performance testing of an annular linear induction pump are presented. The pump electromagnetically pumps liquid metal through a circuit specially designed to allow for quantification of the performance. Testing was conducted over a range of conditions, including frequencies of 33, 36, 39, and 60 Hz, liquid metal temperatures from 125 to 525 C, and input voltages from 5 to 120 V. Pump performance spanned a range of flow rates from roughly 0.16 to 5.7 L/s (2.5 to 90 gpm), and pressure head less than 1 to 90 kPa (less than 0.145 to 13 psi). The maximum efficiency measured during testing was slightly greater than 6%. The efficiency was fairly insensitive to input frequency from 33 to 39 Hz, and was markedly lower at 60 Hz. In addition, the efficiency decreased as the NaK temperature was raised. The performance of the pump operating on a variable frequency drive providing 60 Hz power compared favorably with the same pump operating on 60 Hz power drawn directly from the electrical grid.
Linear induction accelerators at the Los Alamos National Laboratory DARHT facility
Nath, Subrata [Los Alamos National Laboratory
2010-09-07
The Dual-Axis Radiographic Hydrodynamic Test Facility (DARHT) at Los Alamos National Laboratory consists of two linear induction accelerators at right angles to each other. The First Axis, operating since 1999, produces a nominal 20-MeV, 2-kA single beam-pulse with 60-nsec width. In contrast, the DARHT Second Axis, operating since 2008, produces up to four pulses in a variable pulse format by slicing micro-pulses out of a longer {approx}1.6-microseconds (flat-top) pulse of nominal beam-energy and -current of 17 MeV and 2 kA respectively. Bremsstrahlung x-rays, shining on a hydro-dynamical experimental device, are produced by focusing the electron beam-pulses onto a high-Z target. Variable pulse-formats allow for adjustment of the pulse-to-pulse doses to record a time sequence of x-ray images of the explosively driven imploding mock device. Herein, we present a sampling of the numerous physics and engineering aspects along with the current status of the fully operational dual axes capability. First successful simultaneous use of both the axes for a hydrodynamic experiment was achieved in 2009.
Sprogøe, Jonas; Elkjaer, Bente
2010-01-01
The purpose of this paper is to explore how induction of newcomers can be understood as both organizational renewal and the maintenance of status quo, and to develop ways of describing this in terms of learning.......The purpose of this paper is to explore how induction of newcomers can be understood as both organizational renewal and the maintenance of status quo, and to develop ways of describing this in terms of learning....
Andrzej Rusek
2008-01-01
Full Text Available The mathematical model of cylindrical linear induction motor (C-LIM fed via frequency converter is presented in the paper. The model was developed in order to analyze numerically the transient states. Problems concerning dynamics of ac-machines especially linear induction motor are presented in [1 – 7]. Development of C-LIM mathematical model is based on circuit method and analogy to rotary induction motor. The analogy between both: (a stator and rotor windings of rotary induction motor and (b winding of primary part of C-LIM (inductor and closed current circuits in external secondary part of C-LIM (race is taken into consideration. The equations of C-LIM mathematical model are presented as matrix together with equations expressing each vector separately. A computational analysis of selected transient states of C-LIM fed via frequency converter is presented in the paper. Two typical examples of C-LIM operation are considered for the analysis: (a starting the motor at various static loads and various synchronous velocities and (b reverse of the motor at the same operation conditions. Results of simulation are presented as transient responses including transient electromagnetic force, transient linear velocity and transient phase current.
MAGNETIC INDUCTION DISTRIBUTION IN A LINEAR SYNCHRONUS MOTOR WITH MAGNETIC SUSPENSION
Parkhomenko, D. I.; G.M. Golenkov
2013-01-01
Представлені результати комп'ютерного моделювання та експериментального дослідження розподілу магнітної індукції коаксіально-лінійного синхронного двигуна з магнітним підвісом (КЛСД-МП). Дослідження розподілу магнітної індукції проводилося в магнітному зазорі КЛСД-МП, а також на поверхні бігуна. Results of computer simulation and experimental investigations of magnetic induction distribution in a coaxial linear synchronous motor with magnetic suspension are presented. The magnetic inductio...
王铁成; 李伟力; 孙建伟
2003-01-01
A mathematical model has been built up for compound cage rotor induction machine with the rotor re-sistance and leakage inductance in the model identified through Kalman filtering method. Using the identifiedparameters, simulation studies are performed, and simulation results are compared with testing results.
Advanced concepts. [specific impulse, mass drivers, electromagnetic launchers, and the rail gun
Banks, B. A.
1980-01-01
The relative strengths of those interactions which enable propulsive forces are listed as well as the specific impulse of various propellants. Graphics show the linear synchronous motor of the mass driver, the principle of the direct current electromagnetic launcher, and the characteristics of the rail gun.
Mechanical and quasi-optical design of ECH/ECCD launcher for JT-60SA
Kobayashi, Takayuki, E-mail: kobayashi.takayuki@jaea.go.jp; Moriyama, Shinichi; Isayama, Akihiko; Hiranai, Shinichi; Yokokura, Kenji; Sawahata, Masayuki; Terakado, Masayuki; Wada, Kenji; Sato, Yoshikatsu; Hinata, Jun; Hoshino, Katsumichi; Takahashi, Koji; Kajiwara, Ken; Oda, Yasuhisa; Ikeda, Ryosuke; Sakamoto, Keishi
2015-10-15
Highlights: • We designed high-power, long-pulse, two-frequency launcher for JT-60SA. • The mirror steering structure was improved for easy maintenance. • A full scale mockup of the steering structure moved smoothly. • It was found that the antenna is suitable for two frequency operations. • The total spillover loss of ∼1% was obtained with LP11even mode of 10%. - Abstract: Mechanical and quasi-optical design of an electron cyclotron heating/current drive launcher for JT-60SA is in progress. A full-scale mock-up of the steering structure, which enables linear and rotation motions of the first mirror of the launcher, has been fabricated for cyclic test of the bellows part. Moreover, an improved design enables easy replacement of the bellows for rotation for maintenance. Quasi-optical characteristics of the antenna mirrors have been studied to evaluate its transmission efficiency and beam focusing property. In calculation, it was found that the antenna is applicable to two frequency operation at 110 GHz and 138 GHz. It was quantitatively shown that the transmission efficiency of ∼99% (not including Ohmic loss) is obtained even with the higher order mode (LP{sub 11}{sup even}) fraction of 10% by optimizations of the shape of the first mirror. These results contribute to optimization/finalization of the launcher design toward fabrication of the launcher for JT-60SA.
Kim, Hee Reyoung; Lee, Yong Bum; Kim, Yong Kyun; Nam, Ho Yun [KAERI, Taejon (Korea, Republic of)
1998-07-01
The EM (ElectroMagnetic) pump operated by Lorentz force (J x B) is developed for the sodium coolant circulation of LMFBR (Liquid Metal Fast Breeder Reactors). Design and experimental characterization are carried out on the linear induction EM pump of the narrow annular channel type. The pump which obtains propulsion force resultantly by the three phase symmetric alternating input currents is analyzed by the electrical equivalent circuit method used in the analyses of the induction machines. Then, the equivalent circuit for the pump consists of equivalent variables of primary and secondary resistances and magnetizing and leakage reactances given as functions of pump geometrical and electrical variables by Laithwaithe's standard formulae. Developing pressure-flowrate relation given by pump variables is sought from the balance equation on the circuit. Developing pressure and efficiency of the pump according to the pump variables are analyzed for the pump with a flowrate of 200 l/min. It is shown that pump is mainly characterized by length of the core, diameter of the inner core and channel gap geometrically and by input frequency electrically. Optimum values of pump geometrical and operational variables are determined to maximize the developing force and overall efficiency. The pump has geometrical size of 60 cm in length, 4.27 cm in inner core diameter and electrical input of 6,428 VA and 17 Hz. Optimally designed pump is manufactured by the consideration of material and operational requirements in the chemically-active sodium environment with high temperature of 600 .deg. C. Silicon-iron steel plates with high magnetic permeability in the high temperature are stacked for generation of the high magnetic flux and alumina-dispersion-strengthened-copper bands are used as exciting coils. Each turn of coil is insulated by asbestos band to protect electrical short in the high temperature. Stainless steel which can be compatible with sodium is selected as structural
Morizane, Toshimitsu; Kimura, Noriyuki
The ordinary experimental equipment has a long stroke or a large cylindrical rotating secondary side in order to measure the drive characteristics of Linear Induction Motor (LIM). In this paper, we propose the measurement method of the drive characteristics of LIM with the experimental equipment implemented a disc-shaped secondary side. This method makes the experimental equipment smaller in size. It has been shown that the drive characteristics of LIM can be successfully measured.
Atikian, Haig A; Anlage, Steven M; Majedi, A Hamed
2010-01-01
We report the experimental demonstration of linear kinetic-inductive photoresponse of thin-film YBa2Cu3O7-{\\delta} (YBCO) meander-line structures, where the photoresponse amplitude, full-width-half-maximum (FWHM), and rise-time are bilinear in the incident optical power and bias current. This bilinear behavior reveals a trade off between obtaining high responsivity and high speed photodetection. We also report a rise-time as short as 29ps in our photoimpedance measurements.
Mass Estimate for a Lunar Resource Launcher Based on Existing Terrestrial Electromagnetic Launchers
Gordon Roesler
2013-06-01
Full Text Available Economic exploitation of lunar resources may be more efficient with a non-rocket approach to launch from the lunar surface. The launch system cost will depend on its design, and on the number of launches from Earth to deliver the system to the Moon. Both of these will depend on the launcher system mass. Properties of an electromagnetic resource launcher are derived from two mature terrestrial electromagnetic launchers. A mass model is derived and used to estimate launch costs for a developmental launch vehicle. A rough manufacturing cost for the system is suggested.
Future reusable space launcher systems - A European view
Reichert, Rudi G.
Plans for future, reusable space launcher systems in Europe, beyond Ariane V/Hermes, are discussed. A family of launch vehicles, known as the European Advanced Rocket Launchers (EARLs), is presented. Technical and performance data for the EARL concept are given and the cost of development and operating the launchers is estimated. Also, the EARL concept is compared with other planned and existing concepts, including the Saenger launcher.
Rail Inductance Calculations for Some Simple Current Distributions,
1986-02-01
Kowalenko ABSTRACT In this study, an expression for the inductance per unit length of the rails for a railgun -type electromagnetic launcher (EML) is...this report is unlimited. ,EYWORDS Electric guns, Electromagnetic launchers Railgun accelerators Current distribution Equations of motion ’ :.A1M... capacitor bank of an electromagnetic launcher, F d separation of the rails, m dt differential vector length element E(O) total initial energy stored by
Electromagnetic coilgun launcher for space applications
Turman, B.N.; Lipinski, R.J. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185-1182 (United States)
1996-03-01
A ground-based electrically-powered launcher could significantly reduce the complexity and cost of space launches for moderate-weight payloads. The electromagnetic launch complex could greatly reduce the amount of fuels handling, reduce the turn-around time between launches, allow more concurrence in launch preparation, reduce the manpower requirements for launch vehicle preparation and increase the reliability of launch by using more standardized vehicle preparations. The launch requires high acceleration, so the satellite package must be hardened. This paper presents results of a study to estimate the required launcher parameters, and estimate the cost of such a launch facility. This study is based on electromagnetic gun technology which is constrained to a coaxial geometry to take advantage of the efficiency of closely-coupled coils. The launcher energy and power requirements fall in the range of 40{endash}260 GJ and 20{endash}400 GW electric. Parametric evaluations have been conducted with a launcher length of 1{endash}2 km, exit velocity of 1{endash}6 km/s, and payloads to low earth orbit of 100{endash}1000 kg. {copyright} {ital 1996 American Institute of Physics.}
Electromagnetic coilgun launcher for space applications
Turman, B.N.; Lipinski, R.J.
1995-10-01
A ground-based electrically-powered launcher could significantly reduce the complexity and cost of space launches for moderate-weight payloads. The EM launch complex could greatly reduce the amount of fuels handling, reduce the turnaround time between launches, allow more concurrence in launch preparation, reduce the manpower requirements for launch vehicle preparation and increase the reliability of launch by using more standardized vehicle preparations. The launch requires high acceleration, so the satellite package must be hardened. This paper presents results of a study to estimate the required launcher parameters, and estimate the cost of such a launch facility. This study is based on electromagnetic gun technology which is constrained to a coaxial geometry to take advantage of the efficiency of closely-coupled coils. The launcher energy and power requirements fall in the range of 40 {minus} 260 GJ and 20 {minus} 400 GW electric. Parametric evaluations have been conducted with a launcher length of 1-2 km, exit velocity of 1-6 kn/s, and payloads to low earth orbit of 100 1000 kg.
Electromagnetic coilgun launcher for space applications
Turman, B. N.; Lipinski, R. J.
1996-03-01
A ground-based electrically-powered launcher could significantly reduce the complexity and cost of space launches for moderate-weight payloads. The electromagnetic launch complex could greatly reduce the amount of fuels handling, reduce the turn-around time between launches, allow more concurrence in launch preparation, reduce the manpower requirements for launch vehicle preparation and increase the reliability of launch by using more standardized vehicle preparations. The launch requires high acceleration, so the satellite package must be hardened. This paper presents results of a study to estimate the required launcher parameters, and estimate the cost of such a launch facility. This study is based on electromagnetic gun technology which is constrained to a coaxial geometry to take advantage of the efficiency of closely-coupled coils. The launcher energy and power requirements fall in the range of 40-260 GJ and 20-400 GW electric. Parametric evaluations have been conducted with a launcher length of 1-2 km, exit velocity of 1-6 km/s, and payloads to low earth orbit of 100-1000 kg.
Polzin, K. A.; Pearson, J. B.; Webster, K.; Godfoy, T. J.; Bossard, J. A.
2013-01-01
Results of performance testing of an annular linear induction pump that has been designed for integration into a fission surface power technology demonstration unit are presented. The pump electromagnetically pushes liquid metal (NaK) through a specially-designed apparatus that permits quantification of pump performance over a range of operating conditions. Testing was conducted for frequencies of 40, 55, and 70 Hz, liquid metal temperatures of 125, 325, and 525 C, and input voltages from 30 to 120 V. Pump performance spanned a range of flow rates from roughly 0.3 to 3.1 L/s (4.8 to 49 gpm), and pressure heads of <1 to 104 kPa (<0.15 to 15 psi). The maximum efficiency measured during testing was 5.4%. At the technology demonstration unit operating temperature of 525 C the pump operated over a narrower envelope, with flow rates from 0.3 to 2.75 L/s (4.8 to 43.6 gpm), developed pressure heads from <1 to 55 kPa (<0.15 to 8 psi), and a maximum efficiency of 3.5%. The pump was supplied with three-phase power at 40 and 55 Hz using a variable-frequency motor drive, while power at 55 and 70 Hz was supplied using a variable-frequency power supply. Measured performance of the pump at 55 Hz using either supply exhibited good quantitative agreement. For a given temperature, the peak in efficiency occurred at different flow rates as the frequency was changed, but the maximum value of efficiency was relative insensitive within 0.3% over the frequency range tested, including a scan from 45 to 78 Hz. The objectives of the FSP technology project are as follows:5 • Develop FSP concepts that meet expected surface power requirements at reasonable cost with added benefits over other options. • Establish a nonnuclear hardware-based technical foundation for FSP design concepts to reduce overall development risk. • Reduce the cost uncertainties for FSP and establish greater credibility for flight system cost estimates. • Generate the key nonnuclear products to allow Agency
Solid Launcher Dynamical Analysis and Autopilot Design
Ping Sun
2011-02-01
Full Text Available The dynamics of a small solid launch vehicle has been investigated. This launcher consists of a liquid upper stage and three fundamental solid rocket boosters aligned in series. During the ascent flight phase, lateral jets and grid fins are adopted by the flight control system to stable the attitude of the launcher. The launcher is a slender and aerodynamically unstable vehicle with sloshing tanks. A complete set of six-degrees-of-freedom dynamic models of the launcher, incorporation its rigid body, aerodynamics, gravity, sloshing, mass change, actuator, and elastic body, is developed. Dynamic analysis results of the structural modes and the bifurcation locus are calculated on the basis of the presented models. This complete set of dynamic models is used in flight control system design. A methodology for employing numerical optimization to develop the attitude filters is presented. The design objectives include attitude tracking accuracy and robust stability with respect to rigid body dynamics, propellant slosh, and flex. Later a control approach is presented for flight control system of the launcher using both State Dependent Riccati Equation (SDRE method and Fast Output Sampling (FOS technique. The dynamics and kinematics for attitude stable problem are of typical nonlinear character. SDRE technique has been well applied to this kind of highly nonlinear control problems. But in practice the system states needed in the SDRE method are sometimes difficult to obtain. FOS method, which makes use of only the output samples, is combined with SDRE to accommodate the incomplete system state information. Thus, the control approach is more practical and easy to implement. The resulting autopilot can provide stable control systems for the vehicle.
Crespi, M; Messens, E; Caplan, A B; van Montagu, M; Desomer, J
1992-01-01
Rhodococcus fascians is a nocardiform bacteria that induces leafy galls (fasciation) on dicotyledonous and several monocotyledonous plants. The wild-type strain D188 contained a conjugative, 200 kb linear extrachromosomal element, pFiD188. Linear plasmid-cured strains were avirulent and reintroduction of this linear element restored virulence. Pulsed field electrophoresis indicated that the chromosome might also be a linear molecule of 4 megabases. Three loci involved in phytopathogenicity have been identified by insertion mutagenesis of this Fi plasmid. Inactivation of the fas locus resulted in avirulent strains, whereas insertions in the two other loci affected the degree of virulence, yielding attenuated (att) and hypervirulent (hyp) bacteria. One of the genes within the fas locus encoded an isopentenyltranferase (IPT) with low homology to analogous proteins from Gram-negative phytopathogenic bacteria. IPT activity was detected after expression of this protein in Escherichia coli cells. In R.fascians, ipt expression could only be detected in bacteria induced with extracts from fasciated tissue. R.fascians strains without the linear plasmid but containing this fas locus alone could not provoke any phenotype on plants, indicating additional genes from the linear plasmid were also essential for virulence. These studies, the first genetic analysis of the interaction of a Gram-positive bacterium with plants, suggest that a novel mechanism for plant tumour induction has evolved in R.fascians independently from the other branches of the eubacteria. Images PMID:1547783
赵科义; 李治源; 张倩; 向红军; 雷彬; 吕庆敖
2014-01-01
In order to enhance accelerative performance of multi-stage synchronous induction coil launch-er,taking the five-stage synchronous induction coil launcher as an example,based on the conceptions of polarity arrangement manner of driving coil,the influences of polar arrangement manner of driving coil on the accelerative performance are studied by means of time-step finite element analysis in accordance with the coupling of magnetic field and circuit.Research shows that the opposite arrangement manner with the same polarity is more helpful to enhancing launch efficiency than the opposite arrangement manner with different polarity.The reason that leads to enhancing launch efficiency is explored through analysis of the inner magnetic field’s distribution.The correctness of the analysis is validated by comparison of current density in the armature.%为提高多级同步感应线圈发射器的加速性能，以5级同步感应线圈发射器为例，在定义驱动线圈极性相对排列方式的基础上，基于场-路耦合的时步有限元分析方法，研究了驱动线圈极性排列方式对其加速性能的影响，结果表明：驱动线圈同极性相对排列方式更有助于提高发射效率。通过分析内部磁场的分布规律，探讨了驱动线圈同极性相对排列方式改善加速性能的原因，最后通过比较电枢内的感应电流密度的方法验证了分析的正确性。
Tripp, John S.; Daniels, Taumi S.
1990-01-01
The NASA Langley 6 inch magnetic suspension and balance system (MSBS) requires an independently controlled bidirectional DC power source for each of six positioning electromagnets. These electromagnets provide five-degree-of-freedom control over a suspended aerodynamic test model. Existing power equipment, which employs resistance coupled thyratron controlled rectifiers as well as AC to DC motor generator converters, is obsolete, inefficient, and unreliable. A replacement six phase bidirectional controlled bridge rectifier is proposed, which employs power MOSFET switches sequenced by hybrid analog/digital circuits. Full load efficiency is 80 percent compared to 25 percent for the resistance coupled thyratron system. Current feedback provides high control linearity, adjustable current limiting, and current overload protection. A quenching circuit suppresses inductive voltage impulses. It is shown that 20 kHz interference from positioning magnet power into MSBS electromagnetic model position sensors results predominantly from capacitively coupled electric fields. Hence, proper shielding and grounding techniques are necessary. Inductively coupled magnetic interference is negligible.
Tripp, John S.; Daniels, Taumi S.
1990-08-01
The NASA Langley 6 inch magnetic suspension and balance system (MSBS) requires an independently controlled bidirectional DC power source for each of six positioning electromagnets. These electromagnets provide five-degree-of-freedom control over a suspended aerodynamic test model. Existing power equipment, which employs resistance coupled thyratron controlled rectifiers as well as AC to DC motor generator converters, is obsolete, inefficient, and unreliable. A replacement six phase bidirectional controlled bridge rectifier is proposed, which employs power MOSFET switches sequenced by hybrid analog/digital circuits. Full load efficiency is 80 percent compared to 25 percent for the resistance coupled thyratron system. Current feedback provides high control linearity, adjustable current limiting, and current overload protection. A quenching circuit suppresses inductive voltage impulses. It is shown that 20 kHz interference from positioning magnet power into MSBS electromagnetic model position sensors results predominantly from capacitively coupled electric fields. Hence, proper shielding and grounding techniques are necessary. Inductively coupled magnetic interference is negligible.
Input-output linearizing tracking control of induction machine with the included magnetic saturation
Dolinar, Drago; Ljusev, Petar; Stumberger, Gorazd
2003-01-01
The tracking control design of an induction motor, based on input-output linearisation with magnetic saturation included is addressed. The magnetic saturation is represented by a nonlinear magnetising curve for the iron core and is used in the control, the observer of the state variables......, and in the load torque estimator. An input-output linearising control is used to achieve better tracking performances. It is based on the mixed 'stator current - rotor flux linkage' induction motor model with magnetic saturation considered in the stationary reference frame. Experimental results show...... that the proposed input-output linearising tracking control with saturation included behaves considerably better than the one without saturation, and that it introduces smaller position and speed errors, and better motor stiffness on account of the increased computational complexity....
Input-output linearizing tracking control of induction machine with the included magnetic saturation
Dolinar, Drago; Ljusev, Petar; Stumberger, Gorazd
2003-01-01
The tracking control design of an induction motor, based on input-output linearisation with magnetic saturation included is addressed. The magnetic saturation is represented by a nonlinear magnetising curve for the iron core and is used in the control, the observer of the state variables......, and in the load torque estimator. An input-output linearising control is used to achieve better tracking performances. It is based on the mixed 'stator current - rotor flux linkage' induction motor model with magnetic saturation considered in the stationary reference frame. Experimental results show...... that the proposed input-output linearising tracking control with saturation included behaves considerably better than the one without saturation, and that it introduces smaller position and speed errors, and better motor stiffness on account of the increased computational complexity....
Future launchers strategy : the ariane 2010 initiative
Bonnal, Ch.; Eymard, M.; Soccodato, C.
2001-03-01
With the new cryogenic upper stage ESC, the European heavy launcher Ariane 5+ is perfectly suited to the space market envisioned for the coming decade: flexible to cope with any payload and commercially attractive despite a fierce competition. Current Arianespace projections for the following years 2010-2020 indicate two major trends: satellites may still become larger and may require very different final orbits; today's market largely dominated by GEO may well evolve, influenced by LEO operations such as those linked to ISS or by constellations, to remain competitive, the launch cost has to be reduced. The future generation of the European heavy launcher has therefore to focus on an ever increased flexibility with a drastic cost reduction. Two strategies are possible to achieve this double goal: reusable launchers, either partially or totally, may ease the access to space, limiting costly expendable stages; the assessment of their technical feasibility and financial viability is undergoing in Europe under the Future Launchers Technology Program (FLTP), expendable launchers, derived from the future Ariane 5+. This second way started by CNES at the end of year 1999 is called the "Ariane 2010 initiative". The main objectives are simultaneously an increase of 25% in performance and a reduction of 30% in launch cost wrt Ariane 5+. To achieve these very ambitious goals, numerous major modifications are studied: technical improvements : modifications of the Solid Rocket Boosters may consist in filament winding casing, increased loading, simplified casting, improved grain, simplified Thrust Vector Control, … evolution of the Vulcain engine leading to higher efficiency despite a simplified design, flow separation controlled nozzle extension, propellant management of the two cryogenic stages, simplified electrical system, increased standardization, for instance on flanged interfaces and manufacturing processes, operational improvements such as launch cycle simplification
Small Orbital Launcher - Risk Zone Evaluation
Teodor Viorel CHELARU
2015-09-01
Full Text Available The purpose of this paper is to present some aspects regarding two calculus models to evaluate the risk zone of the multistage launcher. Regarding the risk zone, unlike the classic model used for the launcher, we will use a calculus model build on non-inertial frames /taking part to the diurnal rotation (Earth spin. This is necessary to link the risk zone of the launch position, and place it on the map. For the risk zone we will use actually two models: first build in start frame which is more suitable for ascensional guidance phase, and second, built in quasi – velocity frame used for unguided motion especially in descending phase. The discussions will focus around the possibility to find a launching area to be satisfactory in terms of risk conditions arising from the SOL launching.
Next Generation of Launcher & Space Vehicles Batteries
Laroye, J. F.; Brochard, P.; Grassien, J.-Y.; Masgrangeas, D.
2008-09-01
This paper presents several examples of Saft lithium batteries in use onboard launchers & space vehicles: ATV primary lithium manganese dioxide (LiMnO2) batteries and Rosetta primary lithium thionyl chloride (LiSOCl2) batteries as well as the VEGA rechargeable lithium-ion (Li-ion) avionics & thrust vector control (TVC) batteries.It gives an overview of possible chemistries and tradeoff to address these needs.
Additive Layer Manufacturing for Launcher's Applications
Vilanova, J.; Romera, P.; Lasagni, F.; Zorrilla, A.; Perinan, A.
2014-06-01
In the next years the European space industry has the challenge of maintaining its competitiveness in launch vehicles (LV) production, due to the growth of competition worldwide. It has to assure its position developing new applied technologies. In this field the effort is focussed on the production of short series of customized products, like payloads, flight components or launcher parts. ALM (Additive Layer Manufacturing) could be a powerful tool that offers new competitiveness factors for this industry, comprising a set of emerging technologies that are becoming a competitor to forming, casting and machining as well as being utilised directly as a complementary alternative.Originally used for prototypes and models, now ALM becomes a very useful technology capable to fabricate functional parts for the space industrial sector. Its demands on rapid technologies are different to "earth" industries, and they aren't so easily satisfied because space is a field with different requirements depending on its application: launchers, reusable vehicles, satellites, probes, low gravity researches, manned spacecraft, or even moon and planetary exploration.This paper reports on the ALM potential applications, under ESA requirements, exploring the challenges and possibilities for its use in the launchers market, trying to answer two basic questions: the first one, whether ALM is a mature technology to be ready for its use as flight hardware; and the second one, if it can be used to reduce the product cycle, and consequently, the development, production and operational costs.
Gorelov, Y. A.; Lohr, J.; Cengher, M.; Ponce, D.; Ellis, R. A.
2011-10-01
Three fully articulating dual launchers, which can steer the rf beams poloidally and toroidally through +/-20° in each direction, are installed on DIII-D. All are designed and built by PPPL. Each launcher has a fixed focusing mirror followed by a flat steering mirror. Two of the six focusing mirrors were damaged during the past 2 experimental campaigns on DIII-D. The focusing mirrors were made from stainless steel (SS) with a thin layer of copper (Cu) on the surface. Thermal calculation predicts that these mirrors should withstand pulse lengths up to 10 s with incident rf power of 850 kW from the existing gyrotrons. In 2008 local stress cracking of the Cu surface was found on some focusing mirrors. In some cases, the Cu was melted exposing the SS to the rf beam. Rapid thermal runaway and extensive melting resulted. All focusing mirrors were replaced with ones made from solid Al-15 Glidcop construction in 2011. The new design of steerable mirrors was also installed on all launchers. The steering mirrors are moved by dc electric motors, providing full poloidal scans in ~2 s and improved positioning accuracy compared with the air motors previously installed. Work supported by the US DOE under DE-FC02-04ER54698 and DE-AC02-09CH11466.
Final Report Advanced Quasioptical Launcher System
Jeffrey Neilson
2010-04-30
This program developed an analytical design tool for designing antenna and mirror systems to convert whispering gallery RF modes to Gaussian or HE11 modes. Whispering gallery modes are generated by gyrotrons used for electron cyclotron heating of fusion plasmas in tokamaks. These modes cannot be easily transmitted and must be converted to free space or waveguide modes compatible with transmission line systems.This program improved the capability of SURF3D/LOT, which was initially developed in a previous SBIR program. This suite of codes revolutionized quasi-optical launcher design, and this code, or equivalent codes, are now used worldwide. This program added functionality to SURF3D/LOT to allow creating of more compact launcher and mirror systems and provide direct coupling to corrugated waveguide within the vacuum envelope of the gyrotron. Analysis was also extended to include full-wave analysis of mirror transmission line systems. The code includes a graphical user interface and is available for advanced design of launcher systems.
Further investigations of plasma armature performance in the Culham Laboratory HTF rail launcher
Herring, N.; Spikings, C. R.; Oxley, C. M.; Beacham, J. R.; Putley, D.
1993-01-01
This paper presents the results from an experimental investigation of plasma armature behavior in the Culham Laboratory HTF rail launcher. The object of this work was to gain further insight into the conditions which lead to the formation of secondary plasma arcs in the rail launcher. The railgun was operated with a 1 cm square bore formed from glass reinforced epoxy insulators and either stainless steel or copper rails. A 1 MJ, 8 kV capacitor bank was used as the power supply; this was arranged in five 200 kJ modules. The modules were sequentially fired, to produce a current waveform approximating to a linear ramp in the railgun. B-dot probes were used to measure the behavior of the plasma armatures in the launcher. A number of calibration checks were performed to assess the quality of the B-dot probe measurements, with regard to both spatial resolution and rail current measurement. Experimental results were obtained with projectile muzzle velocities ranging from 1.5 km/s to 3.0 km/s, two free arc shots also occurred during the test series. The results show that the launcher performed much better with copper rails than with stainless steel rails. The results also show that the glass epoxy insulators performed much better than the acetyl copolymer material previously used in HTF.
Mellah HACEN
2012-08-01
Full Text Available The induction machine, because of its robustness and low-cost, is commonly used in the industry. Nevertheless, as every type of electrical machine, this machine suffers of some limitations. The most important one is the working temperature which is the dimensioning parameter for the definition of the nominal working point and the machine lifetime. Due to a strong demand concerning thermal monitoring methods appeared in the industry sector. In this context, the adding of temperature sensors is not acceptable and the studied methods tend to use sensorless approaches such as observators or parameters estimators like the extended Kalman Filter (EKF. Then the important criteria are reliability, computational cost ad real time implementation.
Kikuma, T.; Tomita, M.; Ishiyama, A. [Waseda Univ., Tokyo (Japan)
1999-11-10
For the purpose of we examining the effect of characteristics and ac loss under real machine operating environment of the alternating current superconductivity winding for a realization of the superconductive AC machine vessel, cylindrical shortness first linear guiding motor which used NbTi/CuNi superconducting cable for the primary winding was produced experimentally. The coil number was increased from 6 in 14 this time, and the optimization of the primary current was done, and the improvement on characteristics was attempted. Here, starting torque characteristics, quenching detection protection control circuit are reported. (NEDO)
Action induction due to visual perception of linear motion in depth.
Classen, Claudia; Kibele, Armin
2017-01-01
Visually perceived motion can affect observers' motor control in such a way that an intended action can be activated automatically when it contains similar spatial features. So far, effects have been mostly demonstrated with simple displays where objects were moving in a two-dimensional plane. However, almost all actions we perform and visually perceive in everyday life are much more complex and take place in three-dimensional space. The purpose of this study was to examine action inductions due to visual perception of motion in depth. Therefore, we conducted two Simon experiments where subjects were presented with video displays of a sphere (simple displays, experiment 1) and a real person (complex displays, experiment 2) moving in depth. In both experiments, motion direction towards and away from the observer served as task irrelevant information whereas a color change in the video served as relevant information to choose the correct response (close or far positioned response key). The results show that subjects reacted faster when motion direction of the dynamic stimulus was corresponding to the spatial position of the demanded response. In conclusion, this direction-based Simon effect is modulated by spatial position information, higher sensitivity of our visual system for looming objects, and a high salience of objects being on a collision course.
Kapusta, A.B.; Shamota, V.P.
1979-04-01
Laminar flow of an electrically conducting viscous incompressible fluid through the gap between two nonconducting, thin, and infinitely long coaxial cylinders is considered. The inner cylinder is filled with a ferromagnetic medium and the surface of the outer cylinder carries a distributed electric load of a uniform current density. The traveling external magnetic field in this problem is replaced with the uniform magnetic field of a long ring magnet moving parallel to the axis of the cylinders at a certain velocity. The continuity equation for the magnetic field reduces the system of second-degree differential MHD equations to a simpler form, with the Hartmann number and the magnetic Reynolds number as well as the N/sub Eu/(Euler).N/sub Re/(Reynolds) complex as the only parameters. The velocity distribution is found on the basis of the appropriate boundary conditions, for N/sub Ha/ = 2 and N/sub Ha/ is not equal to 2, respectively, and subsequently also the distribution of magnetic induction. The solution is exact and simply arrived at, applicable to any value of the Hartmann number or of other parameters. Numerical calculations indicate that large positive pressure gradients result in a high flow intensity at the outer wall, because the density of electromagnetic forces decreases along the radius. 1 reference, 3 figures.
Fernandes Neto, Tobias Rafael
2012-06-28
guide way (induction rail or stationary magnets), and the energy and information should be transmitted contactless to the active vehicle. Regarding the features of the material handling application, the short or long primary topology can be used. Short primary linear drives on passive track are advantageous in material handling applications, where high precision, moderate dynamic, very long track and closed paths are required. Nevertheless, depending on the requirements of the section, the costs can be reduced considerably by using a simple induction rail at the long transporting sections, instead of permanent magnets on the track. Therefore, in this thesis a combined operation of permanent magnet linear synchronous motor (PMLSM) and linear induction motor (LIM) is applied to operate the short primary as vehicle, avoiding adjustment or releasing of the material during the drive cycle. In summary, the passive track will consist of two section types: a high thrust force section (processing station) with PMLSM and a low thrust force section with LIM (transporting section). To the author's knowledge, using two operation modes (PMLSM / LIM) in the same drive is a new approach. A theoretical and experimental study was conducted to assess the feasibility of employing the short primary linear motor for a flexible manufacturing system, in which a contactless energy transmission provides the basic power and an ultracapacitor (UC) storage system provides the peak power. The system uses a bidirectional DC-DC converter between the ultracapacitor bank and the DC-link, to make sure that the ultracapacitor can store the braking energy and supply the peak power demanded by the active vehicle. A control strategy has been developed for controlling the ultracapacitor to deliver the peak of power, to charge, to protect against overvoltage and to recover the energy generated when the vehicle is braking. A control strategy for the transition between the two operation modes (PMLSM / LIM
Ammar, Abdelkarim; Bourek, Amor; Benakcha, Abdelhamid
2017-03-01
This paper presents a nonlinear Direct Torque Control (DTC) strategy with Space Vector Modulation (SVM) for an induction motor. A nonlinear input-output feedback linearization (IOFL) is implemented to achieve a decoupled torque and flux control and the SVM is employed to reduce high torque and flux ripples. Furthermore, the control scheme performance is improved by inserting a super twisting speed controller in the outer loop and a load torque observer to enhance the speed regulation. The combining of dual nonlinear strategies ensures a good dynamic and robustness against parameters variation and disturbance. The system stability has been analyzed using Lyapunov stability theory. The effectiveness of the control algorithm is investigated by simulation and experimental validation using Matlab/Simulink software with real-time interface based on dSpace 1104.
Kunwar Aditya
2016-11-01
Full Text Available The extended describing function (EDF is a well-known method for modelling resonant converters due to its high accuracy. However, it requires complex mathematical formulation effort. This paper presents a simplified non-linear mathematical model of series-series (SS compensated inductive power transfer (IPT system, considering zero-voltage switching in the inverter. This simplified mathematical model permits the user to derive the small-signal model using the EDF method, with less computational effort, while maintaining the accuracy of an actual physical model. The derived model has been verified using a frequency sweep method in PLECS. The small-signal model has been used to design the voltage loop controller for a SS compensated IPT system. The designed controller was implemented on a 3.6 kW experimental setup, to test its robustness.
Elliott, D. G.
1977-01-01
Measurements of reaction rail currents, reaction rail voltages, and airgap magnetic fields in tests of the Linear Induction Motor Research Vehicle (LIMRV) were compared with theoretical calculations from the mesh/matrix theory. It was found that the rail currents and magnetic fields predicted by the theory are within 20 percent of the measured currents and fields at most motor locations in most of the runs, but differ by as much as a factor of two in some cases. The most consistent difference is a higher experimental than theoretical magnetic field near the entrance of the motor and a lower experimental than theoretical magnetic field near the exit. The observed differences between the theoretical and experimental magnetic fields and currents do not account for the differences of as much as 26 percent between the theoretical and experimental thrusts.
DENG Jiang-ming; CHEN Te-fang; CHEN Chun-yang
2015-01-01
An adaptive current compensation control for a single-sided linear induction motor (SLIM) with nonlinear disturbance observer was developed. First, to maintaint-axis secondary component flux constant with consideration of the specially dynamic eddy-effect (DEE) of the SLIM, a instantaneously tracing compensation ofm-axis current component was analyzed. Second, adaptive current compensation based on Taylor-discretization algorithm was proposed. Third, an effective kind of nonlinear disturbance observer (NDOB) was employed to estimate and compensate the undesired load vibrations, then the robustness of the control system could be guaranteed. Experimental verification of the feasibility of the proposed method for an SLIM control system was performed, and it showed that the proposed adaptive compensation scheme with NDOB could significantly promote speed dynamical response and minimize speed ripple under the conditions of external load coupled vibrations and unavoidable feedback control variables measured errors, i.e., current and speed.
Electron beam dynamics in the long-pulse, high-current DARHT-II linear induction accelerator
Ekdahl, Carl A [Los Alamos National Laboratory; Abeyta, Epifanio O [Los Alamos National Laboratory; Aragon, Paul [Los Alamos National Laboratory; Archuleta, Rita [Los Alamos National Laboratory; Cook, Gerald [Los Alamos National Laboratory; Dalmas, Dale [Los Alamos National Laboratory; Esquibel, Kevin [Los Alamos National Laboratory; Gallegos, Robert A [Los Alamos National Laboratory; Garnett, Robert [Los Alamos National Laboratory; Harrison, James F [Los Alamos National Laboratory; Johnson, Jeffrey B [Los Alamos National Laboratory; Jacquez, Edward B [Los Alamos National Laboratory; Mccuistian, Brian T [Los Alamos National Laboratory; Montoya, Nicholas A [Los Alamos National Laboratory; Nath, Subrato [Los Alamos National Laboratory; Nielsen, Kurt [Los Alamos National Laboratory; Oro, David [Los Alamos National Laboratory; Prichard, Benjamin [Los Alamos National Laboratory; Rowton, Lawrence [Los Alamos National Laboratory; Sanchez, Manolito [Los Alamos National Laboratory; Scarpetti, Raymond [Los Alamos National Laboratory; Schauer, Martin M [Los Alamos National Laboratory; Seitz, Gerald [Los Alamos National Laboratory; Schulze, Martin [Los Alamos National Laboratory; Bender, Howard A [Los Alamos National Laboratory; Broste, William B [Los Alamos National Laboratory; Carlson, Carl A [Los Alamos National Laboratory; Frayer, Daniel K [Los Alamos National Laboratory; Johnson, Douglas E [Los Alamos National Laboratory; Tom, C Y [Los Alamos National Laboratory; Williams, John [Los Alamos National Laboratory; Hughes, Thomas [Los Alamos National Laboratory; Anaya, Richard [LLNL; Caporaso, George [LLNL; Chambers, Frank [LLNL; Chen, Yu - Jiuan [LLNL; Falabella, Steve [LLNL; Guethlein, Gary [LLNL; Raymond, Brett [LLNL; Richardson, Roger [LLNL; Trainham, C [NSTEC/STL; Watson, Jim [LLNL; Weir, John [LLNL; Genoni, Thomas [VOSS; Toma, Carsten [VOSS
2009-01-01
The DARHT-II linear induction accelerator (LIA) now accelerates 2-kA electron beams to more than 17 MeV. This LIA is unique in that the accelerated current pulse width is greater than 2 microseconds. This pulse has a flat-top region where the final electron kinetic energy varies by less than 1% for more than 1.5 microseconds. The long risetime of the 6-cell injector current pulse is 0.5 {micro}s, which can be scraped off in a beam-head cleanup zone before entering the 68-cell main accelerator. We discuss our experience with tuning this novel accelerator; and present data for the resulting beam transport and dynamics. We also present beam stability data, and relate these to previous stability experiments at lower current and energy.
Induction of apoptosis by high linear energy transfer radiation: role of p53
Coelho, D.; Fischer, B.; Holl, V.; Dufour, P. [Lab. de Cancerologie Experimentale et de Radiobiologie, LCER, Inst. de Recherche contre les Cancers de l' Appareil Digestif, IRCAD, Hopital Civil, Strasbourg CEDEX (France); Denis, J.M.; Gueulette, J. [Lab. de Radiobiologie et de Radioprotection, Faculte de Medecine, Univ. Catholique de Louvain, Bruxelles (Belgium); Bergerat, J.P.; Bischoff, P. [Lab. de Cancerologie Experimentale et de Radiobiologie, LCER, Inst. de Recherche contre les Cancers de l' Appareil Digestif, IRCAD, Hopital Civil, Strasbourg CEDEX (France)
2002-07-01
The involvement of the tumor suppressor p53 gene in the sensitivity of many cell types towards low linear energy transfer (LET) radiation is now well established. However, little information is available on the relationship between p53 status of tumor cells and their ability to undergo apoptosis following exposure to high-LET radiation. Here we present the results of experiments carried out with the human lymphoblastoid cell line TK6 and its p53 knock-out counterpart NH32. Cells were irradiated at doses ranging from 0.25 to 8 Gy with fast neutrons (65 MeV), carbon ions (95 MeV/nucleon), and X rays (15 MV). For both cell lines, the occurrence of apoptosis, determined by the quantification of hypodiploid particles as well as the activation of several caspases, was compared with their sensitivity towards high-LET radiation. Results indicate that p53 is involved in the response of TK6 cells to fast neutrons and carbon ions, as measured by cell proliferation and occurrence of apoptosis. However, p53-deficient cells are still able to undergo apoptosis following irradiation. This suggests that heavy ions and fast neutrons induce cellular damage that is not under the control of p53. The involvement of executioner caspases in high-LET radiation induced apoptosis was also evaluated by use of specific inhibitors. (author)
The ITER EC H&CD upper launcher: Structural design
Spaeh, P.; Aiello, G.; de M. Baar,; Chavan, R.; Elzendoorn, B.; Goodman, T.; Henderson, M.; Kleefeldt, K.; Landis, J. D.; Meier, A.; Ronden, D.; Saibene, G.; Scherer, T.; Schreck, S.; Serikov, A.; Strauss, D.; Vaccaro, A.
2011-01-01
Four ITER EC H&CD (Electron Cyclotron Heating and Current Drive) Upper Launchers will be installed in the ITER Tokamak to counteract plasma instabilities by injection of up to 20 MW of millimeter-wave power at 170 GHz. Each Launcher features a structural system which is equipped with eight b
Conceptual design of the ECH upper launcher system for ITER
Heidinger, R.; Bertizzolo, R.; Bruschi, A.; Chavan, R.; Cirant, S.; Collazos, A.; de M. Baar,; Elzendoorn, B.; Farina, D.; Fischer, U.; Gafert, J.; Gandini, F.; Gantenbein, G.; Goede, A.; Goodman, T.; Hailfinger, G.; Henderson, M.; Kasparek, W.; Kleefeldt, K.; Landis, J. D.; Meier, A.; Moro, A.; Platania, P.; Poli, E.; Ramponi, G.; Saibene, G.; Sanchez, F.; Sauter, O.; Scherer, T.; Serikov, A.; Shidara, H.; Sozzi, C.; Spaeh, P.; Strauss, D.; Udintsev, V.S.; Vaccaro, A.; Zohm, H.; Zucca, C.
2009-01-01
The challenge of developing the conceptual design of the ECH Upper Launcher system for MHD control in the ITER plasmas has been tackled by team of European Associations together with the European Domestic Agency ("F4E"). The launcher system has to meet the following requirements: (a) a mm-
Abbasian Mohsen
2013-02-01
Full Text Available Results of theoretical and experimental research on magnetic induction distribution in the air gap of a coaxially-linear synchronous motor with reciprocal motion within the pole pitch and axial and radial direction of the permanent magnets magnetization are presented.
HAMEDANI, P.
2015-08-01
Full Text Available Accurate vector control of a linear induction motor (LIM drive is a complicated subject because of the end effect phenomenon especially in the field-weakening region. This paper concentrates on a novel field-weakening speed control strategy for LIM drive in which the end effect is taken into account. Considering the end effect, new voltage and current limits have been calculated using the Duncan's model. Accordingly, control strategies such as constant force region, partial field-weakening region, and full field-weakening region have been analytically calculated for the first time in this work. In order to improve the control characteristics of the LIM drive, Fuzzy Logic Controller (FLC has been also implemented. Simulation results manifest the satisfactory resultants of the proposed FLC based LIM in the field-weakening region including fast response, no overshoot, negligible steady-state error, and adaptability to load changes. In addition, a new constant force pattern is introduced in this paper by which the reductions of the LIM thrust due to the end effect will be compensated and thus, the current and voltage amplitudes in steady state will remarkably decrease.
Two-Step Multi-Physics Analysis of an Annular Linear Induction Pump for Fission Power Systems
Geng, Steven M.; Reid, Terry V.
2016-01-01
One of the key technologies associated with fission power systems (FPS) is the annular linear induction pump (ALIP). ALIPs are used to circulate liquid-metal fluid for transporting thermal energy from the nuclear reactor to the power conversion device. ALIPs designed and built to date for FPS project applications have not performed up to expectations. A unique, two-step approach was taken toward the multi-physics examination of an ALIP using ANSYS Maxwell 3D and Fluent. This multi-physics approach was developed so that engineers could investigate design variations that might improve pump performance. Of interest was to determine if simple geometric modifications could be made to the ALIP components with the goal of increasing the Lorentz forces acting on the liquid-metal fluid, which in turn would increase pumping capacity. The multi-physics model first calculates the Lorentz forces acting on the liquid metal fluid in the ALIP annulus. These forces are then used in a computational fluid dynamics simulation as (a) internal boundary conditions and (b) source functions in the momentum equations within the Navier-Stokes equations. The end result of the two-step analysis is a predicted pump pressure rise that can be compared with experimental data.
Design of a high power TM01 mode launcher optimized for manufacturing by milling
Dal Forno, Massimo [SLAC National Accelerator Lab., Menlo Park, CA (United States)
2016-12-15
Recent research on high-gradient rf acceleration found that hard metals, such as hard copper and hard copper-silver, have lower breakdown rate than soft metals. Traditional high-gradient accelerating structures are manufactured with parts joined by high-temperature brazing. The high temperature used in brazing makes the metal soft; therefore, this process cannot be used to manufacture structures out of hard metal alloys. In order to build the structure with hard metals, the components must be designed for joining without high-temperature brazing. One method is to build the accelerating structures out of two halves, and join them by using a low-temperature technique, at the symmetry plane along the beam axis. The structure has input and output rf power couplers. We use a TM01 mode launcher as a rf power coupler, which was introduced during the Next Linear Collider (NLC) work. The part of the mode launcher will be built in each half of the structure. This paper presents a novel geometry of a mode launcher, optimized for manufacturing by milling. The coupler was designed for the CERN CLIC working frequency f = 11.9942 GHz; the same geometry can be scaled to any other frequency.
Computational model for simulation small testing launcher, technical solution
Chelaru, Teodor-Viorel, E-mail: teodor.chelaru@upb.ro [University POLITEHNICA of Bucharest - Research Center for Aeronautics and Space, Str. Ghe Polizu, nr. 1, Bucharest, Sector 1 (Romania); Cristian, Barbu, E-mail: barbucr@mta.ro [Military Technical Academy, Romania, B-dul. George Coşbuc, nr. 81-83, Bucharest, Sector 5 (Romania); Chelaru, Adrian, E-mail: achelaru@incas.ro [INCAS -National Institute for Aerospace Research Elie Carafoli, B-dul Iuliu Maniu 220, 061126, Bucharest, Sector 6 (Romania)
2014-12-10
The purpose of this paper is to present some aspects regarding the computational model and technical solutions for multistage suborbital launcher for testing (SLT) used to test spatial equipment and scientific measurements. The computational model consists in numerical simulation of SLT evolution for different start conditions. The launcher model presented will be with six degrees of freedom (6DOF) and variable mass. The results analysed will be the flight parameters and ballistic performances. The discussions area will focus around the technical possibility to realize a small multi-stage launcher, by recycling military rocket motors. From technical point of view, the paper is focused on national project 'Suborbital Launcher for Testing' (SLT), which is based on hybrid propulsion and control systems, obtained through an original design. Therefore, while classical suborbital sounding rockets are unguided and they use as propulsion solid fuel motor having an uncontrolled ballistic flight, SLT project is introducing a different approach, by proposing the creation of a guided suborbital launcher, which is basically a satellite launcher at a smaller scale, containing its main subsystems. This is why the project itself can be considered an intermediary step in the development of a wider range of launching systems based on hybrid propulsion technology, which may have a major impact in the future European launchers programs. SLT project, as it is shown in the title, has two major objectives: first, a short term objective, which consists in obtaining a suborbital launching system which will be able to go into service in a predictable period of time, and a long term objective that consists in the development and testing of some unconventional sub-systems which will be integrated later in the satellite launcher as a part of the European space program. This is why the technical content of the project must be carried out beyond the range of the existing suborbital
Erixon, K.; Cedervall, B. [Karolinksa Institutet, Stockholm (Sweden)
1995-05-01
Pulsed-field gel electrophoresis has been applied to separate DNA from mouse L1210 cells exposed to X-ray doses of 1 to 50 Gy. Simultaneous separation of marker chromosomes in the range 0.1 to 12.6 Mbp allowed calculation of the size distribution of the radiation-induced fragments. The distribution was consistent with a random induction of double-strand breaks (DSBs). A theoretical relationship between the size distribution of such fragments and the average number of induced breaks was used to calculate the yield and dose response. The DNA distribution was determined by both radiolabeling and fluorescence staining. Two independent methods were use to evaluate the radiation-induced yield of DSBs, both assuming that all DNA is broken at random. In the first method we compared the theoretical and experimental fraction of DNA that is below a given size limit. By this method we estimated the yield to be 0.006-0.007 DSB/GY per million base pairs using the radiolabel and 0.004-0.008 DSB/Gy per million base pairs by fluorescence staining. The dose response was linear in both cases. In the second method we looked only at the size distribution in the resolving part of the gel and compared it to the theoretical distribution. By this method a value of approximately 0.012 DSB/Gy/Mb was found, using fluorescence as a measure of DNA distribution. In a normal diploid mammalian genome of size 60000 Mbp, this is equivalent to a yield of 25-50 DSBs/Gy or 70 DSBs/GY, respectively. The second approach, which looks only at the smaller fragments, may overestimate the yield, while the first approach suffers from uncertainties about the fraction of DNA irreversibly trapped in the well. The assay has the capacity to detect a dose of less than 1 Gy. 58 refs., 10 figs.
Mineo, Hirobumi; Yamaki, Masahiro; Kim, Gap-Sue; Teranishi, Yoshiaki; Lin, Sheng Hsien; Fujimura, Yuichi
2016-09-29
A new laser-control scenario of unidirectional π-electron rotations in a low-symmetry aromatic ring molecule having no degenerate excited states is proposed. This scenario is based on dynamic Stark shifts of two relevant excited states using two linearly polarized stationary lasers. Each laser is set to selectively interact with one of the two electronic states, the lower and higher excited states are shifted up and down with the same rate, respectively, and the two excited states become degenerate at their midpoint. One of the four control parameters of the two lasers, i.e. two frequencies and two intensities, determines the values of all the other parameters. The direction of π-electron rotations, clockwise or counter-clockwise rotation, depends on the sign of the relative phase of the two lasers at the initial time. An analytical expression for the time-dependent expectation value of the rotational angular momentum operator is derived using the rotating wave approximation (RWA). The control scenario depends on the initial condition of the electronic states. The control scenario with the ground state as the initial condition was applied to toluene molecules. The derived time-dependent angular momentum consists of a train of unidirectional angular momentum pulses. The validity of the RWA was checked by numerically solving the time-dependent Schrödinger equation. The simulation results suggest an experimental realization of the induction of unidirectional π-electron rotations in low-symmetry aromatic ring molecules without using any intricate quantum-optimal control procedure. This may open up an effective generation method of ring currents and current-induced magnetic fields in biomolecules such as amino acids having aromatic ring molecules for searching their interactions.
Sharp and the Jules Verne Launcher
Hunter, John; Cartland, Harry
1996-03-01
Lawrence Livermore National Laboratory (LLNL) has built the worlds largest hydrogen gas gun called SHARP, (Super High Altitude Research Project). Originally designed to launch 5 kg to a 450 km altitude, SHARP is configured horizontally at Site 300 in Tracy, California. SHARP is successfully delivering 5 kg scramjets at Mach 9 in aerophysics tests. Some of the results of the scramjet tests are enlightening and are presented insofar as they are relevant to future launches into space. Using a light gas gun to launch payloads into orbit has been analyzed. We look at LEO (Low Earth Orbit), GEO (Geosynchronous Earth Orbit), and LO (Lunar Orbit). We present a conceptual design for a large light gas gun called the Jules Verne Launcher (JVL). The JVL can deliver 3.3 metric tons to a 500 km low earth orbit. We anticipate one launch per day. We present the history of light gas guns, the SHARP design and performance, and the JVL design. Another section is devoted to the vehicle environment and resultant design. Lastly, we present a cost analysis. Our results indicated that the JVL will be able to deliver 1000 metric tons of payload to LEO yearly. The cost will be 5% of the best US rocket delivery cost. This technology will enable the next phase of man's exploration of space.
Calibrating Accelerometers Using an Electromagnetic Launcher
Erik Timpson
2012-05-13
A Pulse Forming Network (PFN), Helical Electromagnetic Launcher (HEML), Command Module (CM), and Calibration Table (CT) were built and evaluated for the combined ability to calibrate an accelerometer. The PFN has a maximum stored energy of 19.25 kJ bank and is fired by a silicon controlled rectifier (SCR), with appropriate safety precautions. The HEML is constructed out of G-10 fiberglass and is designed to accelerate 600 grams to 10 meters per second. The CM is microcontroller based running Arduino Software. The CM has a keypad input and 7 segment outputs of the bank voltage and desired voltage. After entering a desired bank voltage, the CM controls the charge of the PFN. When the two voltages are equal it allows the fire button to send a pulse to the SCR to fire the PFN and in turn, the HEML. The HEML projectile's tip hits a target that is held by the CT. The CT consists of a table to hold the PFN and HEML, a vacuum chuck, air bearing, velocity meter and catch pot. The Target is held with the vacuum chuck awaiting impact. After impact, the air bearing allows the target to fall freely for the velocity meter to get an accurate reading. A known acceleration is determined from the known change in velocity of the target. Thus, if an accelerometer was attached to the target, the measured value can be compared to the known value.
The enhanced ASDEX Upgrade pellet centrifuge launcher
Plöckl, B.; Lang, P. T.
2013-10-01
Pellets played an important role in the program of ASDEX Upgrade serving both for investigations on efficient particle fuelling and high density scenarios but also for pioneering work on Edge Localised Mode (ELM) pacing and mitigation. Initially designed for launching fuelling pellets from the magnetic low field side, the system was converted already some time ago to inject pellets from the magnetic high field side as much higher fuelling efficiency was found using this configuration. In operation for more than 20 years, the pellet launching system had to undergo a major revision and upgrading, in particular of its control system. Furthermore, the control system installed adjacent to the launcher had to be transferred to a more distant location enforcing a complete galvanic separation from torus potential and a fully remote control solution. Changing from a hybrid system consisting of PLC S5/S7 and some hard wired relay control to a state of the art PLC system allowed the introduction of several new operational options enabling more flexibility in the pellet experiments. This article describes the new system architecture of control hardware and software, the operating procedure, and the extended operational window. First successful applications for ELM pacing and triggering studies are presented as well as utilization for the development of high density scenarios.
Calculations supporting HyperVelocity Launcher development
Trucano, T.G.; Chhabildas, L.C.
1993-08-01
Sandia National Laboratories has developed a HyperVelocity Launcher (also referred to as HVL) in which a thin flier plate (nominally 1 mm thick) is launched to velocities in excess of 12 km/s. The length to diameter ratio of these launched flier plates varies from 0.02 to 0.06. The launch technique is based upon using structured, time-dependant, high-pressure, high-acceleration pulses to drive the flier plates. Such pulses are achieved by using a graded-density material to impact a stationary flier. A computational and experimental program at Sandia seeks to extend this technique to allow launching thick plates whose length-to-diameter ratio is 10 to 20 times larger than thin plates. Hydrodynamic codes are used to design modifications to the basic technique. The authors have controlled and used these effects to successfully launch a chunk-flier, consisting of 0.33 gm of titanium alloy, 0.3 cm thick by 0.6 cm in diameter, to a velocity of 10.2 km/s. This is the largest chunky size ever launched at this velocity from a gas gun configuration.
Morizane, Toshimitsu; Iwaki, Kaoru; Kimura, Noriyuki; Taniguchi, Katsunori
We propose a maglev transportation system that has only the Single-sided Linear Induction Motor (SLIM) without the levitation magnet and a novel control method of the attractive force and thrust force of the SLIM by the power source that has different frequency components. In the proposed system, the total force is the sum of the forces generated by the different frequency components. We verified the incoherent characteristics of the attractive force and thrust force by experiment.
Design and Analysis of Steerable ECRH Launcher for SST-1 Tokamak
Mistry Hardik
2017-01-01
A detailed analysis is carried out for the mirrors of the high power launcher. The heat load for the 82 GHz launcher is 2 kW (~1% absorption and for 42 GHz launcher it is 5 kW. For 82 GHz launcher, the maximum steady state surface temperatures of focusing and reflecting mirrors are 315K and 323K and von-mises stresses are within 10 MPa. Similarly for 42 GHz launcher maximum temperatures observed during 500 ms pulse are 301K and 303K for focusing and reflecting mirrors respectively. This paper explains the mechanical and thermal design and analysis of the launcher for the ECRH system.
Bini, Donato; Chicone, Carmen; Mashhoon, Bahram
2008-01-01
We study the linear post-Newtonian approximation to general relativity known as gravitoelectromagnetism (GEM); in particular, we examine the similarities and differences between GEM and electrodynamics. Notwithstanding some significant differences between them, we find that a special nonstationary metric in GEM can be employed to show {\\it explicitly} that it is possible to introduce gravitational induction within GEM in close analogy with Faraday's law of induction and Lenz's law in electrodynamics. Some of the physical implications of gravitational induction are briefly discussed.
Preliminary design of the ITER ECH Upper Launcher
Strauss, D., E-mail: dirk.strauss@kit.edu [Karlsruhe Institute of Technology, Assoc. KIT-EURATOM, D-76021 Karlsruhe (Germany); Aiello, G. [Karlsruhe Institute of Technology, Assoc. KIT-EURATOM, D-76021 Karlsruhe (Germany); Chavan, R. [Centre de Recherches en Physique des Plasmas, CRPP–EPFL, CH-1015 Lausanne (Switzerland); Cirant, S. [Istituto di Fisica del Plasma CNR, Euratom Association, 20125 Milano (Italy); Baar, M. de [FOM, Van Vollenhovenlaan 659, 3527 JP, Utrecht (Netherlands); Farina, D. [Istituto di Fisica del Plasma CNR, Euratom Association, 20125 Milano (Italy); Gantenbein, G. [Karlsruhe Institute of Technology, Assoc. KIT-EURATOM, D-76021 Karlsruhe (Germany); Goodman, T.P. [Centre de Recherches en Physique des Plasmas, CRPP–EPFL, CH-1015 Lausanne (Switzerland); Henderson, M.A. [ITER Organization, 13108 Saint-Paul-lez-Durance (France); Kasparek, W. [Institut für Plasmaforschung, IPF, D-70569 Stuttgart (Germany); Kleefeldt, K. [Karlsruhe Institute of Technology, Assoc. KIT-EURATOM, D-76021 Karlsruhe (Germany); Landis, J.-D. [Centre de Recherches en Physique des Plasmas, CRPP–EPFL, CH-1015 Lausanne (Switzerland); Meier, A. [Karlsruhe Institute of Technology, Assoc. KIT-EURATOM, D-76021 Karlsruhe (Germany); Moro, A.; Platania, P. [Istituto di Fisica del Plasma CNR, Euratom Association, 20125 Milano (Italy); Plaum, B. [Institut für Plasmaforschung, IPF, D-70569 Stuttgart (Germany); Poli, E. [Max-Planck-IPP, Euratom Association, D-85748 Garching (Germany); Ramponi, G. [Istituto di Fisica del Plasma CNR, Euratom Association, 20125 Milano (Italy); Ronden, D. [FOM, Van Vollenhovenlaan 659, 3527 JP, Utrecht (Netherlands); Saibene, G. [Fusion for Energy, Barcelona (Spain); and others
2013-11-15
Highlights: • Front steering mirror design. • Plasma facing blanket shield module/first wall panel design. • Fixed frequency torus CVD diamond window serving as first tritium barrier. • Prototypes and tests of the above key components in the Launcher Handling and Testing Facility. -- Abstract: The design of the ITER electron cyclotron launchers recently reached the preliminary design level - the last major milestone before design finalization. The ITER ECH system contains 24 installed gyrotrons providing a maximum ECH injected power of 20 MW through transmission lines towards the tokamak. There are two EC launcher types both using a front steering mirror; one equatorial launcher (EL) for plasma heating and four upper launchers (UL) for plasma mode stabilization (neoclassical tearing modes and the sawtooth instability). A wide steering angle range of the ULs allows focusing of the beam on magnetic islands which are expected on the rational magnetic flux surfaces q = 1 (sawtooth instability), q = 3/2 and q = 2 (NTMs). In this paper the preliminary design of the ITER ECH UL is presented, including the optical system and the structural components. Highlights of the design include the torus CVD-diamond windows, the frictionless, front steering mechanism and the plasma facing blanket shield module (BSM). Numerical simulations as well as prototype tests are used to verify the design.
Direct Energy Exchange Enhancement in Distributed Injection Light Gas Launchers
Alger, T W; Finucane, R G; Hall, J P; Penetrante, B M; Uphaus, T M
2000-04-06
It is not widely acknowledged or appreciated that conventional, two-stage light-gas launchers do not efficiently apply their high breech pressures to the design intent: accelerating the projectile. Our objective in this project was to carry out the analysis, design, construction, and testing of a new class of launchers that will address this limitation. Our particular application is to expand the pressure range of the conventional, two-stage gas launcher to overlap and validate the pressure regimes previously attainable only with shock waves generated by nuclear explosions, lasers, or multistage conventional explosions. That is, these launchers would have the capability to conduct--in a laboratory setting--high-velocity-impact, equation-of-state (EOS) measurements at up to 2-TPa (20 Mbar) pressure levels in high-Z materials. Our design entailed a new class of distributed-injection, gas-dynamic launchers that are designed to use a boat-tail projectile to overcome the fundamental gas-expansion phenomena known as escape velocity (the Riemann limit). Our program included analytical, numerical, and experimental studies of the fast gas release flow technique that is central to the success of our approach. The analyses led us to believe that, in a typical configuration, the pressure will be effectively applied to the projectile in a time short relative to its few-microsecond traverse time; the experimental program we conducted during FY1999 supported these estimates. In addition, our program revealed dramatic increased efficiency in this process that was previously unknown to the launcher community. The most fundamental practical restrictions on the performance of any gas launcher are the ability of the launcher to (1) contain pressure in a reservoir, and (2) effectively apply that pressure to the base of a moving projectile. Our gas-release test-fixture experiments showed that our design was capable of applying nearly twice the pressure to the projectile that is
The ITER EC H and CD upper launcher: Structural system
Spaeh, Peter, E-mail: peter.spaeh@kit.edu [Karlsruhe Institute of Technology, Institute for Applied Materials, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Aiello, Gaetano; Gessner, Robby; Grossetti, Giovanni; Meier, Andreas; Scherer, Theo; Schreck, Sabine [Karlsruhe Institute of Technology, Institute for Applied Materials, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Serikov, Arkady [Karlsruhe Institute of Technology, Institute for Neutron Physics and Reactor Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Strauss, Dirk; Vaccaro, Alessandro [Karlsruhe Institute of Technology, Institute for Applied Materials, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Weinhorst, Bastian [Karlsruhe Institute of Technology, Institute for Neutron Physics and Reactor Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany)
2013-10-15
Highlights: ► ITER EC H and CD Launcher goes towards final design. ► European consortium founded for bringing the EC H and CD launcher towards final design. ► New design updates for dedicated components of the ITER EC H and CD launcher. -- Abstract: After approval of the preliminary design of the ITER EC H and CD Upper Launcher, ECHUL-CA, a consortium of several European research institutes, was founded to pool resources for approaching the final design. At the end of 2011 the consortium has signed a 2 years contract with F4E to go ahead with the work on the launcher. The contract deals with design work on both the port plug, forming the structural system, and the mm-wave-system, which injects the RF-power into the plasma. Within the period of this contract all components being part of the Tritium confinement, of which the closure plate, the support flange, the diamond windows and the waveguide feed-throughs are the most outstanding ones, will get the status of the final design. Important steps to be done for the structural system are the optimization of the mechanical behavior of the launcher, leading to minimum deflections of the port plug during plasma disruptions and optimum seismic resistance. To reduce the effect of halo currents it was decided to recess the first wall of 100 mm compared to the regular blanket tangent. This recess requires substantial changes of the cooling system and the thermo-hydraulic design of the launcher. Also the layout of the shielding arrangement and the integration of the mm-wave system need significant revision. Moreover manufacturing aspects and enhanced remote handling capability are taken into account. For the final design also quality aspects must be considered; thus the design is elaborated with respect to applicable codes and standards, material specifications, risk analyses and the RAMI (reliability, availability, maintainability and inspectability) analysis to guarantee maximum performance of the device. This paper
Inductively-Activated Short-Interval Timer
Wiker, Gordon A.; Wells, George H., Jr.
1989-01-01
Timing circuit in pneumatically launched projectile triggers explosive charge in projectile at specified delay after launch. Both power and control signals coupled inductively to timer from stationary launcher circuitry. Eliminates need for direct electrical contacts, which are unreliable and generate sparks that trigger explosive accidentally. Inductive coupling also provides higher reliability in field operation than contacts. Concept useful in such other safety-related applications as remotely or automatically controlling flow of bottled flammable gas.
An Engineering Design STEM Project: T-Shirt Launcher
Fantz, Todd D.; Grant, Melva R.
2013-01-01
The article offers information on making technology education students interested in science and mathematics through the use of a T-shirt launcher design project. This project was designed for junior and senior level high school students who have completed or are currently taking physics and precalculus. The project involves designing an…
Energy stores and switches for rail-launcher systems
Weldon, W. F.; Zowarka, R. C.; Marshall, R. A.
1983-01-01
An overview of existing switch and power supply technology applicable to space launch, a new candidate pulsed power supply for Earth-to-space rail launcher duty, the inverse railgun flux compressor, and a set of switching experiments to study further the feasibility of Earth-to-space launch are discussed.
An Engineering Design STEM Project: T-Shirt Launcher
Fantz, Todd D.; Grant, Melva R.
2013-01-01
The article offers information on making technology education students interested in science and mathematics through the use of a T-shirt launcher design project. This project was designed for junior and senior level high school students who have completed or are currently taking physics and precalculus. The project involves designing an…
Performance of an induction coil gun
Shokair, I.R.; Cowan, M.; Kaye, R.J.; Marder, B.M.
1993-10-01
Performance of an electromagnetic induction launcher is considered for three types of armatures. These are: Solid, 1-element wound and 16-element wound aluminum ar natures. The one element wound armature has uniform current density throughout. Because of the radial distribution of the current density, the wound armature can withstand field reversal (working against embedded flux in the armature) and still maintain low temperature. Slingshot simulations were performed, for several configurations. Best performance was obtained for a single element wound armature with two field reversals. For a 60 kg projectile, 10.5 cm coil inner radius and 5.5 cm coil build, the velocity after 50 meters of launcher length (670 stages) exceeded 3.5 km/sec with an overall efficiency of about 45%. For the same parameters the solid and 16-element wound armatures reach a velocity of about 3.3 km/sec after 800 stages (60 meters of launcher length) but without field reversal. A velocity of 3.5 km/sec is possible after 60 meters of launcher length with the 16-element wound armature with one field reversal, but the temperature is close to the melting temperature of aluminum. In all simulations with a solid armature, melting of some of the surface material occurs. However, it is shown that most of the melting occurs after contribution has been made to the forward going pressure, that is, melting does not affect the electrical performance of the launcher. The effect of coil firing tune jitter on launcher performance is also considered and is found to be very small for realistic perturbations. For {plus_minus}2 {mu}-secs random jitter, the reduction in the final velocity for a 60 meter launcher with a solid armature is less than 0.1% and the increase in temperature is only 2%. This result holds for all types of armatures.
线性代数教学中的归纳与演绎方法%On Inductive and Deductive Methods in Teaching of Linear Algebra
王颖; 南基洙
2013-01-01
A list of charming characteristics of Linear Algebra includes lots concepts ,abstract contents ,and rigorous logics .It is difficult for students to seize the key points of knowledge in their learning processes .T his paper discusses the application of inductive and deductive methods in teaching of linear algebra .Some cases are illustrated to show the use of the two methods .%针对线性代数概念多、内容抽象、逻辑性强等特点，介绍归纳和演绎方法在线性代数教学中的应用，并借助具体案例加以说明。
Progress of the ECRH Upper Launcher design for ITER
Strauss, D., E-mail: dirk.strauss@kit.edu [Karlsruhe Institute of Technology, Assoc. KIT-EURATOM, D-76021 Karlsruhe (Germany); Aiello, G. [Karlsruhe Institute of Technology, Assoc. KIT-EURATOM, D-76021 Karlsruhe (Germany); Bruschi, A. [Istituto di Fisica del Plasma CNR, Euratom Association, 20125 Milano (Italy); Chavan, R. [Centre de Recherches en Physique des Plasmas, CRPP–EPFL, CH-1015 Lausanne (Switzerland); Farina, D.; Figini, L. [Istituto di Fisica del Plasma CNR, Euratom Association, 20125 Milano (Italy); Gagliardi, M.; Garcia, V. [Fusion for Energy, Barcelona (Spain); Goodman, T.P. [Centre de Recherches en Physique des Plasmas, CRPP–EPFL, CH-1015 Lausanne (Switzerland); Grossetti, G. [Karlsruhe Institute of Technology, Assoc. KIT-EURATOM, D-76021 Karlsruhe (Germany); Heemskerk, C. [Heemskerk Innovative Technology, Merelhof 2, 2172 HZ Sassenheim (Netherlands); Henderson, M.A. [ITER Organization, 13108 Saint-Paul-lez-Durance (France); Kasparek, W. [Institut für Plasmaforschung, IPF, D-70569 Stuttgart (Germany); Krause, A.; Landis, J.-D. [Centre de Recherches en Physique des Plasmas, CRPP–EPFL, CH-1015 Lausanne (Switzerland); Meier, A. [Karlsruhe Institute of Technology, Assoc. KIT-EURATOM, D-76021 Karlsruhe (Germany); Moro, A.; Platania, P. [Istituto di Fisica del Plasma CNR, Euratom Association, 20125 Milano (Italy); Plaum, B. [Institut für Plasmaforschung, IPF, D-70569 Stuttgart (Germany); Poli, E. [Max-Planck-IPP, Euratom Association, D-85748 Garching (Germany); and others
2014-10-15
The design of the ITER ECRH system provides 20 MW millimeter wave power for central plasma heating and MHD stabilization. The system consists of an array of 24 gyrotrons with power supplies coupled to a set of transmission lines guiding the beams to the four upper and the equatorial launcher. The front steering upper launcher design described herein has passed successfully the preliminary design review, and it is presently in the final design stage. The launcher consists of a millimeter wave system and steering mechanism with neutron shielding integrated into an upper port plug with the plasma facing blanket shield module (in-vessel) and a set of ex-vessel waveguides connecting the launcher to the transmission lines. Part of the transmission lines are the ultra-low loss CVD torus diamond windows and a shutter valve, a miter bend section and the feedthroughs integrated in the plug closure plate. These components are connected by corrugated waveguides and form together the first confinement system (FCS). In-vessel, the millimeter-wave system includes a quasi-optical beam propagation system including four mirror sets and a front steering mirror. The millimeter wave system is integrated into a specifically optimized upper port plug providing structural stability to withstand plasma disruption forces and the high heat load from the plasma side with a dedicated blanket shield module. A recent update in the ITER interface definition has resulted in the recession of the upper port plug first wall panels, which is now integrated into the design. Apart from the millimeter wave system the upper port plug houses also a set of shield blocks which provide neutron shielding. An overview of the actual ITER ECRH Upper Launcher is given together with some highlights of the design.
基于DSP的直线感应电动机矢量控制%The Vector Control of Linear Induction Motor Based on DSP
卞林玉; 陈志辉
2012-01-01
A mathematical analysis of a doubled-sided, short secondary linear induction motor was made, and an e-quivalent circuit and the establishment of the mathematical model were given out. Because of the dynamic vertical end effect of the linear induction motor, the end effect function was added according to vector control theory of the induction motor. Hie model of the control system based on MATLAB/Simulink was established. And much study about vector control was done to verify the feasibility and correctness of control system model mentioned. The program of the vector control system of linear induction motor based on TMS320F2812 was compiled,and the relevant experiments and analysis were done. Hie location , reciprocating motion and other functions were mainly achieved.%以双边长初级短次级直线感应电动机为研究对象,根据样机的实际结构分析推导了电机的数学模型.直线电机存在由于铁心开断而引起的端部效应,在采用矢量控制策略时,需要对基于旋转感应电动机的矢量控制策略进行修正,建立了基于MATLAB/Simulink的系统模型,进行了直线感应电动机矢量控制的仿真研究,验证了控制方案的可行性与正确性.在理论分析和仿真验证的基础上,设计了基于TMS320F2812的全数字矢量控制系统的控制系统硬件电路,进行了系统实验,实现了电机定位、往返运动等功能.
Oudalova, A.A.; Geras' kin, S.A.; Dikarev, V.G.; Nesterov, Y.B.; Dikareva, N.S
2002-07-01
The low dose region was evaluated for meristem cells of spring barley. A study of the cytogenetic damage in the low dose range was carried out to determine the genuine shape of the dose curve. The relationship between the frequency of aberrant cells and the absorbed dose is shown to be non-linear with a site at low doses within which the cytogenetic damage exceeds the control level significantly and does not depend on dose value. Within the tested exposure region, the aberrant cell frequency is found to decrease with increasing dose rate, but the shape of the dose curve remained invariable. The piecewise linear model fits the experimental data much better than the linear one. (author)
Vidal, P.E.
2004-12-15
This study deals with linear and non-linear control strategies applied to the rotation speed feedback of a doubly fed induction machine (DFIM), whose stator and rotor windings are connected to two Pulse Width Modulation voltage source inverters. We choose to distribute the active powers between the stator and the rotor following a certain proportionality ratio. This leads to guarantee, in steady state operation, a stator and rotor angular frequencies sharing. This distribution is initially assured by two shared angular frequencies controllers, and in a second time by the means of the Park transformation angles directly. Two models are established: the first express the currents, and the second is linked with the fluxes. The simulations results of the linear control (field oriented control), and non-linear control (sliding mode control), show a good independence between the main flux and the torque. An experimental validation is also presented. The results presented show the satisfactory DFIM flux control. Special attention is paid to the active power dispatching. (author)
Bini, Donato; Cherubini, Christian; Chicone, Carmen; Mashhoon, Bahram
2008-01-01
We study the linear post-Newtonian approximation to general relativity known as gravitoelectromagnetism (GEM); in particular, we examine the similarities and differences between GEM and electrodynamics. Notwithstanding some significant differences between them, we find that a special nonstationary metric in GEM can be employed to show {\\it explicitly} that it is possible to introduce gravitational induction within GEM in close analogy with Faraday's law of induction and Lenz's law in electrod...
牵引直线感应电机推力优化控制的研究%Torque-optimized Control Strategy for Linear Induction Motor Drive
顾赟; 杨中平
2011-01-01
本文利用涡流损耗分析的方法,推导了考虑纵向边端效应的直线感应电机动态数学模型.通过对直线电机控制特点的分析,设计了LIM矢量控制器.在此基础上,提出了一种以推力最大为目标的牵引直线感应电机推力优化控制方法.Matlab/Simulink仿真结果与直线电机牵引传动实验平台的实验结果表明,采用优化控制后直线电机在输入一定时能够提高输出推力,输入功率越小推力提高越明显,同时系统具有良好的调速性能,验证了本方案在牵引直线电机控制上的可行性.%The dynamic LIM mathematical model inclusive of the longitudinal end-effect is derived by analysis of eddy current losses. The field orientation control scheme is developed through further analysis of the difference of linear motor and rotary motor control. On this basis, the linear induction motor traction thrust optimization control method is derived with the objective to acquire the maximum thrust. The Matlab/Simulink simulation results and experimental results of the linear motor traction and drive test platform show as follows: After applying optimization control, the thrust output of the linear motor is raised corresponding to a certain input; the smaller the input power, the more obvious the thrust output lifting; and the system demonstrates good speed control performance. These results verify the feasibility of the proposed scheme in linear traction motor control.
Characteristic analysis of no-load speed of linear induction motor%直线感应电机空载速度特性分析
司纪凯; 艾立旺; 韩俊波; 许孝卓; 上官璇峰
2014-01-01
There is a special phenomenon in linear arc-shaped motor and linear induction motor with fi-nite-length primary. Their no-load rotating ( translational ) speeds exceed the so-called synchronous speed. With a simplified single-sided linear induction motor( SLIM) as the research object, the mathe-matical model of the motor was established by using Maxwell's equations. Air gap and end region magnet-ic field distribution considering dynamic longitudinal end effect was calculated. A physical quantity “E-quivalent electromagnetic pole pitch” considering the dynamic longitudinal end effects was proposed and correction coefficients corresponding to mechanical pole pitch with different number of poles was given. Finally, the rationality of the analytical method and validity of correction coefficients were verified by fi-nite element method( FEM) simulation software and prototype testing. It can be concluded that no-load speed does not exceed the synchronous speed calculated by “Equivalent electromagnetic pole pitch” and just exceeds the synchronous speed calculated by mechanical pole pitch. It has some informative values to the theoretical research and development of linear induction motor.%针对初级有限长的直线弧形感应电机和直线感应电动机的特殊现象---空载速度超过所谓的同步速度,以简化的单边直线感应电机( single-sided linear induction motor,SLIM)模型为研究对象；利用麦克斯韦方程组建立了该电机的数学解析模型,计算了动态纵向端部效应影响下电机气隙磁场和端部磁场分布；提出了考虑纵向端部效应的新物理量“等效电磁极距”,给出不同极数时机械极距的修正系数。通过有限元法( finite element method,FEM)仿真和样机试验验证了解析法结论的合理性和修正系数的正确性,得出结论：空载速度并未超过由等效电磁极距计算而得的同步速度,只是超过由机械极距计算而得的
Voorhies, Coerte V.
1993-01-01
The problem of estimating a steady fluid velocity field near the top of Earth's core which induces the secular variation (SV) indicated by models of the observed geomagnetic field is examined in the source-free mantle/frozen-flux core (SFI/VFFC) approximation. This inverse problem is non-linear because solutions of the forward problem are deterministically chaotic. The SFM/FFC approximation is inexact, and neither the models nor the observations they represent are either complete or perfect. A method is developed for solving the non-linear inverse motional induction problem posed by the hypothesis of (piecewise, statistically) steady core surface flow and the supposition of a complete initial geomagnetic condition. The method features iterative solution of the weighted, linearized least-squares problem and admits optional biases favoring surficially geostrophic flow and/or spatially simple flow. Two types of weights are advanced radial field weights for fitting the evolution of the broad-scale portion of the radial field component near Earth's surface implied by the models, and generalized weights for fitting the evolution of the broad-scale portion of the scalar potential specified by the models.
Design and manufacturing of the ITER ECRH Upper launcher mirrors
Sanchez, Francisco; Bertizzolo, Robert; Chavan, Rene; Collazos, Andres; Landis, Jean Daniel
2008-01-01
Four of the 16 ITER upper port plugs will be devoted to electron cyclotron resonance heating (ECRH) in order to control the magneto-hydrodynamic (MHD) instabilities. In order to achieve the stabilisation of the neoclassical tearing modes (NTM) and sawtooth oscillation, a deposition of a very localized and peaked current density profile over a broad poloidal steering range is required. In the present optical configuration eight 2MW mm-wave beams enter each of the four upper launchers (UL) thro...
Advanced launcher for lower hybrid current drive on Tore Supra
Bibet, Ph.; Kazarian, F.; Agarici, G.; Deck, C.; Doceul, L.; Froissard, Ph.; Garampon, L.; Goniche, M.; Mailloux, J.; Portafaix, C.; Rey, G.; Samaille, F.; Simoncini, J.; Tonon, G. [Association Euratom-CEA Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Durand, D.; Vial, A.; Rousset, E. [SICN, Centre Technique de Veurey (France)
1998-07-01
A new advanced launcher is being built for LHCD on Tore Supra in order to inject 4 MW for pulse of 1000 s at 3.7 GHz and a power density of 25 MW/m{sup 2}. After a description of the antenna, the construction procedure is depicted. The main constraints are given. Results of the RF tests of the first multijunction andmode converter are presented. (author)
Modeling the capillary discharge of an electrothermal (ET) launcher
Least, Travis
Over the past few decades, different branches of the US Department of Defense (DoD) have invested at improving the field ability of electromagnetic launchers. One such focus has been on achieving hypervelocity launch velocities in excess of 7 km/s for direct launch to space applications [1]. It has been shown that pre-injection is required for this to be achieved. One method of pre-injection which has promise involves using an electro-thermal (ET) due to its ability to achieve the desired velocities with a minimal amount of hot plasma injected into the launcher behind the projectile. Despite the demonstration of pre-injection using this method, polymer ablation is not very well known and this makes it challenging to predict how the system will behave for a given input of electrical power. In this work, the rate of ablation has been studied and predicted using different models to generate the best possible characteristic curve. [1] - Wetz, David A., Francis Stefani, Jerald V. Parker, and Ian R. McNab. "Advancements in the Development of a Plasma-Driven Electromagnetic Launcher." IEEE TRANSACTIONS ON MAGNETICS 45.1 (2009): 495--500. IEEE Xplore. Web. 18 Aug. 2012.
Shaw, Eric J.
2001-01-01
This paper will report on the activities of the IAA Launcher Systems Economics Working Group in preparations for its Launcher Systems Development Cost Behavior Study. The Study goals include: improve launcher system and other space system parametric cost analysis accuracy; improve launcher system and other space system cost analysis credibility; and provide launcher system and technology development program managers and other decisionmakers with useful information on development cost impacts of their decisions. The Working Group plans to explore at least the following five areas in the Study: define and explain development cost behavior terms and concepts for use in the Study; identify and quantify sources of development cost and cost estimating uncertainty; identify and quantify significant influences on development cost behavior; identify common barriers to development cost understanding and reduction; and recommend practical, realistic strategies to accomplish reductions in launcher system development cost.
Thermal and non-thermal particle interaction with the LHCD launchers in Tore Supra
Ekedahl, A. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France)]. E-mail: annika.ekedahl@cea.fr; Goniche, M. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Balorin, C. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Basiuk, V. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Bibet, Ph. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Chantant, M. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Colas, L. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Delpech, L. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Desgranges, C. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Eriksson, L.-G. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Joffrin, E. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Kazarian, F. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Lowry, C. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Moreau, Ph. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Petrzilka, V. [Association Euratom-IPP.CR, Za Slovankou 3, P.O. Box 17, 182 21 Praha 8 (Czech Republic); Portafaix, C. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Prou, M. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France); Roche, H. [Association Euratom-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 Saint Paul-lez-Durance (France)
2007-06-15
The interaction between the lower hybrid current drive (LHCD) launchers and the plasma has been studied during long pulse, high power operation in the Tore Supra tokamak. The main diagnostics used for characterising the plasma-launcher interaction are calorimetry of the energy extracted by the launchers and infrared (IR) imaging of the launchers and their side limiters. The calorimetry has allowed to identify three different heat sources on the LHCD launchers, namely the RF losses in the waveguides, a fraction ({approx}0.8%) of the total injected energy and, finally, fast ion losses during ion cyclotron resonance heating (ICRH), accounting for {approx}1% of the injected ICRH energy. The interaction by fast ions is identified by infrared imaging of the LHCD launchers as a localised hotspot on the ion drift side, below or at the mid-plane.
Kikuma, T.; Ishiyama, A. [Waseda Univ., Tokyo (Japan)
2000-05-29
For the purpose of examining the characteristics (effect of stability and ac loss by the higher harmonic wave etc.) of an alternating current superconductivity winding under a real machine operating environment of the super-conductive AC machine vessel, authors produced a cylindrical shortness first linear guiding motor (SCLIM) which used the NbTi/CuNi super-conducting cable for the first excitation winding experimentally. In this study, the evaluation of the start up thrust and operation confirmation of the quenching detection protection circuit were carried out using the produced SCLIM. In the quenching detection protection control circuit, the first excitation winding was divided into an internal layer and an outer layer, and both layers were excited in the 2 layer division and a quenching detection protection circuit was installed on the 2 layers respectively. The circuit of a part of fact by this of the phase in which the quench was generated and observed was cut off, and the operation would be able to be continued in part of the remainder of the phase and other two phases. Here, it is to cut off the quenched phase from the circuit, when the phase current becomes zero, and the other effect on the phase is held as small as possible. (NEDO)
High-Efficiency Helical Coil Electromagnetic Launcher and High Power Hall-Effect Switch
2008-02-29
Expressions for electromagnetic force, efficiency, back-voltage, and kinetic power are derived and given in terms of electrical circuit parameters. Launcher...helical electromagnetic launcher which is subsequently compared to a one-turn augmented railgun and a conventional railgun operating at comparable scale...Efficiency Helical Coil Electromagnetic Launcher and High Power Hall-Effect Switch by T.G. Engel, W.C. Nunnally, and J.M. Gahl Center for Energy Conversion
Wermuth, P J; Jimenez, S A
2014-01-01
The gadolinium-based contrast agent (GdBCA) Omniscan activates human macrophages through Toll-like receptor (TLR)-4 and TLR-7 signalling. To explore the mechanisms responsible we compared the ability of linear and macrocyclic GdBCA to induce a type I interferon signature and a proinflammatory/profibrotic phenotype in normal human monocytes in vitro. Expression of genes associated with type I interferon signalling and inflammation and production of their corresponding proteins were determined. Both linear and macrocyclic GdBCA stimulated expression of multiple type I interferon-regulated genes and the expression of numerous chemokines, cytokines and growth factors in normal human peripheral blood monocytes. There was no correlation between the magnitude of the measured response and the Gd chelate used. To explore the mechanisms responsible for GdBCA induction of fibrosis in nephrogenic systemic fibrosis (NSF) in vitro, normal human dermal fibroblasts were incubated with GdBCA-treated monocyte culture supernatants and the effects on profibrotic gene expression were examined. Supernatants from monocytes exposed to all GdBCA stimulated types I and III collagen, fibronectin and α-smooth muscle actin (α-SMA) expression in normal dermal fibroblasts. The results indicate that the monocyte activation induced by GdBCA may be the initial step in the development of GdBCA associated fibrosis in NSF.
罗芳; 赵国明; 王远波
2001-01-01
阐述了直流感应电动机的基本原理，介绍了由西南交通大学研制的磁浮车演示线上的直线感应电动机的主要设计参数及特点，并对其试验结果加以分析。%The paper expounds the principle of linear induction motor and introduces the main design parameters and specialties of the linear induction motor in a maglevvehicle exhibit line,designed and produced by Southwest Jiaotong University,and analyzes the result data of some experiments．
Kang, Bongmun; Yoon, Ho-Sung
2015-02-01
Recently, microalgae was considered as a renewable energy for fuel production because its production is nonseasonal and may take place on nonarable land. Despite all of these advantages, microalgal oil production is significantly affected by environmental factors. Furthermore, the large variability remains an important problem in measurement of algae productivity and compositional analysis, especially, the total lipid content. Thus, there is considerable interest in accurate determination of total lipid content during the biotechnological process. For these reason, various high-throughput technologies were suggested for accurate measurement of total lipids contained in the microorganisms, especially oleaginous microalgae. In addition, more advanced technologies were employed to quantify the total lipids of the microalgae without a pretreatment. However, these methods are difficult to measure total lipid content in wet form microalgae obtained from large-scale production. In present study, the thermal analysis performed with two-step linear temeperature program was applied to measure heat evolved in temperature range from 310 to 351 °C of Nostoc sp. KNUA003 obtained from large-scale cultivation. And then, we examined the relationship between the heat evolved in 310-351 °C (HE) and total lipid content of the wet Nostoc cell cultivated in raceway. As a result, the linear relationship was determined between HE value and total lipid content of Nostoc sp. KNUA003. Particularly, there was a linear relationship of 98% between the HE value and the total lipid content of the tested microorganism. Based on this relationship, the total lipid content converted from the heat evolved of wet Nostoc sp. KNUA003 could be used for monitoring its lipid induction in large-scale cultivation. Copyright © 2014 Elsevier Inc. All rights reserved.
Optimal Design of HTS Linear Induction Motors%高温超导直线感应电机的优化设计
赵佳; 郑琼林; 张威; 方进; 刘友梅
2011-01-01
The structure design and primary winding arrangment of a high temperature superconductor linear induction motor（HTS LIM） are discussed in detail.The relationship curve between the critical current and background field of the HTS tape is given.Using the finite element analysis software Maxwell the electromagnetic properties of the HTS LIM are analyzed.And the key parameters such as the primary coil number,primary slot height and primary slot width are sweeped and optimized.The influence of these key parameters on the thrust force,primary slot leakage flux and critical current of the HTS LIM is also analyzed.Based on the analysis the optimal design method is proposed.According to the structure and the parameters of the HTS LIM a prototype linear induction motor with copper primary windings is manufactured.The thrust force of the prototype motor is tested with different currents and speeds.Comparing the test results with the simulation results a modified coefficient of the thrust is obtained.This coefficient is meaningful for studying the thrust force with different motor parameters.%详细讨论了高温超导直线感应电机的结构设计和初级绕组排列方式,给出了高温超导带材临界电流和背景磁场的关系曲线。采用Maxwell有限元电磁分析软件对高温超导直线感应电机进行了详细的电磁分析,并对初级绕组匝数、初级铁心槽高和初级铁心槽宽等关键参数进行了参数扫描和优化,分析了它们对电机电磁力、初级槽漏磁通和电机临界电流的影响,提出了高温超导直线感应电机的优化设计方法。根据得到的高温超导直线感应电机优化设计参数制造了一台完全相同的铜绕组实验样机,测试了样机在不同电流和速度下的推力,对比相同条件下得到的有限元电磁仿
Analysis of a Series of Electromagnetic Launcher Firings,
1987-06-01
m I current in the rallgun circuit, A 10 current In the railgun circuit at the Instant of crowbarring of the capacitor bank, A I1 current passing...the results obtained from the digitiser. The power source (1,51 for the electromagnetic launcher used in the RPIP series consisted of a capacitor bank...0.3 pH. In all of the firings reported here the capacitor bank was charged to 6.00 t 0.03 kV. The cadmium-copper rails used in the RAPID railgun were
Developing a Launch Package for the PEGASUS Launcher
2016-01-01
Railguns are capable to far exceed the muzzle energies of current naval deck guns. Therefore one of the most promising scenario for the future application of railguns in naval warfare is the long range artillery. Hypervelocity projectiles being propelled to velocities above 2 km/s reach targets at distances of 200 km or more. At the French-German Research Institute the PEGASUS launcher is used for investigations with respect to this scenario. The 6 m long barrel has a square caliber of 40 mm....
British government, industry agree to fund Hotel launcher studies
Brown, D. A.
1986-02-01
A program status assessment is presented for the horizontal takeoff and landing 'Hotol' single-stage-to-orbit space launcher, for which parallel, two-year airframe and propulsion system proof-of-concept studies have been approved. A two-year initial development program for the airframe would be followed by a four-year development and manufacturing phase that would begin upon the propulsion system concept's successful demonstration. Flight trials could begin in 1996. A number of significant modifications have already been made to the initial design concept, such as to the foreplanes, afterbody, engine intake, and orbital control system.
Height Adjustment Technology for Induction Plate of Linear Motor in Line%直线电机线路感应板高度调整技术探讨
席雷
2012-01-01
感应板是直线电机线路中的重要设备，文章对感应板高度调整工作的特点进行了介绍，并进一步分析了感应板高度变化的原因，在此基础上提出了感应板高度调整工作的若干建议。%The induction plate is an important component of linear motor, the paper describes characteristics of the induction plate height adjustment work, and further analyzes the reasons of induction plate height changes. Based on it, recommendations are made on the induction plate height adjustment work.
Mazarakis, M.G.; Poukey, J.W.; Maenchen, J.E.
1997-06-01
The authors present the design, analysis, and results of the high-brightness electron beam experiments currently under investigation at Sandia National Laboratories. The anticipated beam parameters are the following: 8--12 MeV, 35--50 kA, 30--60 ns FWHM, and 0.5-mm rms beam radius. The accelerators utilized are SABRE and HERMES III. Both are linear inductive voltage adders modified to higher impedance and fitted with magnetically immersed foil less electron diodes. In the strong 20--50 Tesla solenoidal magnetic field of the diode, mm-size electron beams are generated and propagated to a beam stop. The electron beam is field emitted from mm-diameter needle-shaped cathode electrode and is contained in a similar size envelop by the strong magnetic field. These extremely space charge dominated beams provide the opportunity to study beam dynamics and possible instabilities in a unique parameter space. The SABRE experiments are already completed and have produced 30-kA, 1.5-mm FWHM electron beams, while the HERMES-III experiments are on-going.
Chunk projectile launch using the Sandia Hypervelocity Launcher Facility
Chhabildas, L.C.; Trucano, T.G.; Reinhart, W.D.; Hall, C.A.
1994-07-01
An experimental technique is described to launch an intact ``chunk,`` i.e. a 0.3 cm thick by 0.6 cm diameter cylindrical titanium alloy (Ti-6Al-4V) flyer, to 10.2 km/s. The ability to launch fragments having such an aspect ratio is important for hypervelocity impact phenomenology studies. The experimental techniques used to accomplish this launch were similar but not identical to techniques developed for the Sandia HyperVelocity Launcher (HVL). A confined barrel impact is crucial in preventing the two-dimensional effects from dominating the loading response of the projectile chunk. The length to diameter ratio of the metallic chunk that is launched to 10.2 km/s is 0.5 and is an order of magnitude larger than those accomplished using the conventional hypervelocity launcher. The multi-dimensional, finite-difference (finite-volume), hydrodynamic code CTH was used to evaluate and assess the acceleration characteristics i.e., the in-bore ballistics of the chunky projectile launch. A critical analysis of the CTH calculational results led to the final design and the experimental conditions that were used in this study. However, the predicted velocity of the projectile chunk based on CTH calculations was {approximately} 6% lower than the measured velocity of {approximately}10.2 km/S.
RL-10 Based Combined Cycle For A Small Reusable Single-Stage-To-Orbit Launcher
Balepin, Vladimir; Price, John; Filipenco, Victor
1999-01-01
This paper discusses a new application of the combined propulsion known as the KLIN(TM) cycle, consisting of a thermally integrated deeply cooled turbojet (DCTJ) and liquid rocket engine (LRE). If based on the RL10 rocket engine family, the KLIN (TM) cycle makes a small single-stage-to-orbit (SSTO) reusable launcher feasible and economically very attractive. Considered in this paper are the concept and parameters of a small SSTO reusable launch vehicle (RLV) powered by the KLIN (TM) cycle (sSSTO(TM)) launcher. Also discussed are the benefits of the small launcher, the reusability, and the combined cycle application. This paper shows the significant reduction of the gross take off weight (GTOW) and dry weight of the KLIN(TM) cycle-powered launcher compared to an all-rocket launcher.
Flux Synthesizing Linear Induction Motor
古関, 隆章
1992-01-01
報告番号: 甲09471 ; 学位授与年月日: 1992-03-30 ; 学位の種別: 課程博士 ; 学位の種類: 博士(工学) ; 学位記番号: 博工第2808号 ; 研究科・専攻: 工学系研究科電気工学専攻
Research of Driving Circuit in Coaxial Induction Coilgun
Yadong Zhang
2013-09-01
Full Text Available Power supply is crucial equipment in coaxial induction coil launcher.Configuration of the driving circuit influences the efficiency of the coil launcher directly.This paper gives a detailed analysis of the properties of the driving circuit construction based on the capacitor source. Three topologies of the driving circuit are compared including oscillation circuit, crowbar circuit and half-wave circuit. It is proved that which circuit has the better efficiency depends on the detailed parameters of the experiment, especially the crowbar resistance. Crowbar resistor regulates not only efficiency of the system, but also temperature rise of the coil. Electromagnetic force (EMF applied on the armature will be another question which influences service condition of the driving circuits. Oscillation circuit and crowbar circuit should apply to the asynchronous induction coil launcher and synchronous induction coil launcher, respectively. Half-wave circuit is seldom used in the experiment. Although efficiency of the half-wave circuit is very high, the speed of the armature is low. A simple independent half-wave circuit is suggested in this paper. Generally speaking, the comprehensive property of crowbar circuit is the most practical in the three typical circuits. Conclusions of the paper could provide guidelines for practice.
Peeler, C; Bronk, L [UT MD Anderson Cancer Center, Houston, TX (United States); UT Graduate School of Biomedical Sciences at Houston, Houston, TX (United States); Taleei, R; Guan, F; Patel, D; Titt, U; Mirkovic, D; Grosshans, D; Mohan, R [UT MD Anderson Cancer Center, Houston, TX (United States); Stewart, R [University of Washington School of Medicine, Seattle, WA (United States)
2015-06-15
Purpose: High throughput in vitro experiments assessing cell survival following proton radiation indicate that both the alpha and the beta parameters of the linear quadratic model increase with increasing proton linear energy transfer (LET). We investigated the relative biological effectiveness (RBE) of double-strand break (DSB) induction as a means of explaining the experimental results. Methods: Experiments were performed with two lung cancer cell lines and a range of proton LET values (0.94 – 19.4 keV/µm) using an experimental apparatus designed to irradiate cells in a 96 well plate such that each column encounters protons of different dose-averaged LET (LETd). Traditional linear quadratic survival curve fitting was performed, and alpha, beta, and RBE values obtained. Survival curves were also fit with a model incorporating RBE of DSB induction as the sole fit parameter. Fitted values of the RBE of DSB induction were then compared to values obtained using Monte Carlo Damage Simulation (MCDS) software and energy spectra calculated with Geant4. Other parameters including alpha, beta, and number of DSBs were compared to those obtained from traditional fitting. Results: Survival curve fitting with RBE of DSB induction yielded alpha and beta parameters that increase with proton LETd, which follows from the standard method of fitting; however, relying on a single fit parameter provided more consistent trends. The fitted values of RBE of DSB induction increased beyond what is predicted from MCDS data above proton LETd of approximately 10 keV/µm. Conclusion: In order to accurately model in vitro proton irradiation experiments performed with high throughput methods, the RBE of DSB induction must increase more rapidly than predicted by MCDS above LETd of 10 keV/µm. This can be explained by considering the increased complexity of DSBs or the nature of intra-track pairwise DSB interactions in this range of LETd values. NIH Grant 2U19CA021239-35.
The ITER EC H and CD upper launcher: EM disruption analyses
Vaccaro, A., E-mail: Alessandro.Vaccaro@kit.edu [Karlsruhe Institute of Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe, Germany, Institut für Angewandte Materialien - Angewandte Werkstoffphysik (Germany); Aiello, G.; Grossetti, G.; Meier, A.; Scherer, T.A.; Schreck, S.; Späh, P.; Strauß, D. [Karlsruhe Institute of Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe, Germany, Institut für Angewandte Materialien - Angewandte Werkstoffphysik (Germany); Saibene, G.; Cavinato, M. [Fusion for Energy, C/Josep Pla 2, Torres Diagonal Litoral-B3, E-08019 Barcelona (Spain)
2013-10-15
In the frame of the new grant started in November 2011 between Fusion for Energy (F4E) and the ECHUL-CA consortium, the development process of the Electron Cyclotron Heating and Current Drive (EC H and CD) upper launcher (UL) in ITER has moved a step toward the final design phase. Based on the 2009 preliminary design review version, the new configuration of the UL now features a thicker single-wall mainframe (up to 90 mm), a recessed first wall panel (100 mm, to reduce the impact of halo currents) and a new arrangement of the internal shield blocks. The main design drivers for the structural components are still the electromagnetic (EM) loads, which need to be reassessed for the new configuration of the UL. In this paper the results of a new EM 20° sector model of ITER, specialized for the UL, are shown. Six different disruption scenarios are considered in this work: upward linear (36 ms) and exponential (36 ms) vertical displacement events (VDE), upward linear (36 ms) and exponential (16 ms) major disruptions (MD), category II upward slow and slow–fast VDEs. Comparing the analyses’ results allowed to define a set of structural loads to be used as a reference for the forthcoming structural calculations.
Characterization of the supersonic wake of a generic space launcher
Schreyer, A.-M.; Stephan, S.; Radespiel, R.
2017-03-01
The wake flow of a generic axisymmetric space-launcher model is investigated experimentally for flow cases with and without propulsive jet to gain insight into the wake-flow phenomena at a supersonic stage of the flight trajectory which is especially critical with respect to dynamic loads on the structure. Measurements are performed at Mach 2.9 and a Reynolds number Re D = 1.3 × 106 based on model diameter D. The nozzle exit velocity of the jet is at Mach 2.5, and the flow is moderately underexpanded ( p e/ p ∞ = 5.7). The flow topology is described based on velocity measurements in the wake by means of particle image velocimetry and schlieren visualizations. Mean and fluctuating mass-flux profiles are obtained from hot-wire measurements, and unsteady wall-pressure measurements on the main-body base are performed simultaneously. This way, the evolution of the wake flow and its spectral content can be observed along with the footprint of this highly dynamic flow on the launcher main-body base. For the case without propulsive jet, a large separated zone is forming downstream of the main body shoulder, and the flow is reattaching further downstream on the afterbody. The afterexpanding propulsive jet (air) causes a displacement of the shear layer away from the wall, preventing the reattachment of the flow. In the spectral analysis of the baseline case, a dominant frequency around St D = 0.25 is found in the pressure-fluctuation signal at the main-body base of the launcher. This frequency is related to the shedding of the separation bubble and is less pronounced in the presence of the propulsive jet. In the shear layer itself, the spectra obtained from the hot-wire signal have a more broadband low-frequency content, which also reflects the characteristic frequency of turbulent structures convected in the shear layer, a swinging motion ( St D = 0.6), as well as the radial flapping motion of the shear layer ( St D = 0.85), respectively. Moving downstream along the
许金; 马伟明; 鲁军勇; 孙兆龙; 张育兴; 饶金
2011-01-01
对于分段供电直线感应电动机,其定子绕组互感存在较大的不对称,基于磁动势理论,推导出分段供电直线感应电机的单相绕组磁动势分布,明确了分段供电直线电机磁动势分布的特点.基于单相绕组的磁动势分布,推导了分段供电直线电机气隙磁场分布的解析表达式,有限元仿真结果验证了解析分析的正确性.根据电机磁场的分析结果,推导了电机各相绕组自感和互感表达式,说明了分段供电直线电机互感不对称的机理,在此基础上得到的电机电感矩阵和阻抗矩阵说明了电机互感和阻抗不对称的规律,试验结果验证了所推导电机阻抗矩阵的正确性.%For segment-powered linear inductive motor, there is major asymmetry among the mutual inductance of stator windings. Based on magnetic motive force theory, this paper derived the magnetic motive force distribution of single-phase winding of the segment-powered linear inductive motor, and confirmed the characteristics of magnetic motive force distribution of the segment-powered linear inductive motor. Based on the magnetic motive force distribution of single-phase winding, the analytic expressions of air-gap field distribution of the segment-powered linear motor were derived, and the finite element simulation results verified the analytic results. Based on analysis results of motor magnetic field, the self-inductance and mutual-inductance expressions of each phase winding of motor were derived, which explained the mechanics of the mutual inductance asymmetry of segment-powered linear motor. And based on that, the obtained motor inductance matrix and resistance matrix illustrated the asymmetry laws of the motor mutual inductance and resistance. Finally the experiment results verified the correctness of the derived motor resistance matrix.
高温超导直线感应电机的电磁优化设计%Electromagnetic optimization design of a HTS linear induction motor
赵佳; 张威; 方进; 杨中平; 郑琼林; 刘友梅
2011-01-01
主要给出了高温超导直线感应电机的设计和电磁分析方法.根据常规直线感应电机设计公式,结合遗传算法和约束条件得到了当前条件下最优化的电机参数.由于高温超导直线感应电机的特殊性,很难用公式法直接得到准确的电机优化参数,因此用有限元电磁分析软件Ansoft对得到的电机模型进行了性能分析,并根据分析结果修改电机参数,直到电机性能满足设计要求为止.%This paper presents the design and the electromagnetic analysis of a high-temperature superconductor (HTS) linear induction motor (LIM). According to the formulas of the normal LIM, combined with genetic algorithm and the constraints, the optimal motor parameters could be obtained. Due to the particularity of the HTS LIM, it's difficult to obtain the accurate motor optimization parameters using the formula method directly. So the model of the motor is made and analyzed using the finite element electromagnetic analysis software Ansoft. According to the results the parameters of the motor will be modified until the characteristics meet the design requirements.
Small-bore hypervelocity Electromagnetic Launcher research facility
Hurn, T. W.; Chapelle, S.; Lupan, S. P.; Holland, L.; Homeyer, W. G.; Rawls, J. M.
1993-01-01
A small-bore hypervelocity Electromagnetic Launcher laboratory research facility has been developed which has launched a 2-g projectile to a velocity in excess of 3.5 km/sec. This turn-key laboratory includes a 1 cm, square-bore railgun with a helium gas preaccelerator; a modular 328 kJ capacitor bank; a fiber-optically linked programmable logic control system with a graphical operator interface; a data acquisition system with current, magnetic, and projectile position diagnostics; and a flight range which provides in-flight velocity measurements and safely stops and contains the projectile. The control system fires the preaccelerator and, on receipt of an optical signal, fires the capacitor bank modules simultaneously or in a staggered mode. Armature separation and stalling limit the overall performance of the system. Changes in pulse shape and bore materials significantly improved performance. Attention is given to methods used to minimize armature separation and improve performance.
Electromagnetic Armor Based on the Principles of Reconnection Electromagnetic Launcher
Yu Haiqing; Li Weitao; Gao Haizhen
2015-01-01
Active electromagnetic armor is the latest concept of defense system, and it is highly probable for this technology to be applied to many domains such as future tanks, armored vehicles and the armor of warships. The studies on active electromagnetic defense technology in the world have a history of decades. But, there still exist bottlenecks and the interceptor is one of them. This paper studies the problem of interceptors based on the principles of reconnection electromagnetic launcher and presents a kind of simulation model of it. A small scale laboratory model is made, and related experimental researches and theoretical analyses have been carried out when the projectiles are different kinds of material and shape. Satisfactory results are reached and agree with the theoretical analyses.
Parametric Optimization of Electrothermal-chemical (ETC) Launchers
陈林; 徐敏; 宋盛义; 仇旭
2002-01-01
The research on a 30 mm electrothermal-chemical (ETC) gun including theoretical simulation and experimental results is presented in this paper. The predictions of the theoretical model which is composed of three parts (i.e., pulse forming network, plasma generator and interior ballistics) are in good agreement with the experiments. In addition, we have performed some liquid propellant and solid propellant experiments, respectively. Among the solid propellant experiments, we have investigated the ignition modes of propellant and high velocity launchers. As a result, the 25: 75 mixture of octane and hydrogen peroxide has a better effect than other liquid propellants. When the propellants are ignited nearby the bottom of projectile in chamber by using an ullage tube connected with the plasma generator, the kinetic energy of projectile will increase, while the chamber pressure will decrease. With a total input electrical energy of 180 k J, the exit velocity of projectile is up to 2.1 km/s or so.
Valade, Laurent, E-mail: laurent.valade@cea.fr; Ekedahl, Annika; Colas, Laurent; Goniche, Marc; Hillairet, Julien [CEA, IRFM, F-13108 Saint Paul-lez-Durance (France); Fuchs, Vladimir; Petrzilka, Vaclav [Institute of Plasma Physics, AS CR, Prague (Czech Republic); Li, Miaohui; Zhang, Bin [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)
2015-12-10
The effect of the detailed waveguide spectrum on the electron acceleration has been studied for the 3.7 GHz LHCD launchers in Tore Supra, i.e. the ITER-like passive-active multijunction (PAM) launcher and the fully-active-multijunction (FAM) launcher, using test electron modelling technique. The detailed launched antenna wave spectrum is used as input to the code that computes the dynamics of the electrons in the electric field. Comparison with the LHCD launchers in EAST, operating at 2.45 GHz and 4.6 GHz, has also been made. The simulations show that the PAM-design generates lower flux of fast electrons than FAM-launchers, this could be the consequence of the wider waveguide of PAM-launcher (14.65 mm for Tore-Supra) than FAM-launcher (8 mm for Tore-Supra)
High Voltage Smart Power Module For Fault-Tolerant Launcher Applications
Richard Debrouwere
2017-01-01
This paper presents the design of a low cost and highly integrated smart power module (SPM intended to be used into launchers applications, embedding technologies and components from automotive world and being mainly producible by large-scale industry.
Stankevich, S. V.; Shvetsov, G. A.
2014-09-01
This paper presents the results of numerical simulation of the Joule heating of the armature and rails in rail launchers of metal bodies with one or two augmenting rails generating an external magnetic field. The ultimate projectile velocity is calculated under the assumption that the Joule heating of the armature and rails during acceleration does not exceed the melting temperature of the materials of which they are made. It is shown that, with an appropriate choice of the position of the coils generating the augmenting magnetic field with respect to the launcher channel and the current magnitude in them, the heat load on the rails and armature in electromagnetic launchers of solids can be substantially reduced and the ultimate kinematic characteristics of these launchers in crisis-free regimes can be considerably increased.
Design and Analysis of Steerable ECRH Launcher for SST-1 Tokamak
Mistry Hardik; Shukla B K
2017-01-01
.... So focusing and plane mirror combination is used to launch focused beam in plasma. Thus an ECRH launcher consists of metallic profiled and plane mirror, UHV compatible vacuum barrier window and a UHV gate valve...
Baldesi, Gianluigi; Toso, Mario
2012-06-01
Virtual simulation is currently a key activity in the specification, design, verification and operations of space systems. System modelling and simulation support in fact a number of use cases across the spacecraft development life cycle, including activities such as system design validation, software verification and validation, spacecraft unit and sub-system test activities, etc. As the reliance on virtual modelling, simulation and justification has substantially grown in recent years, a more coordinated and consistent approach to the development of such simulation tools across project phases can bring substantial benefit in reducing the overall space programme schedule, risk and cost. By capitalizing on the ESA (European Space Agency) Structures and Mechanisms division's strong expertise in dynamics (multibody software), a generic multibody flight simulator was created to simulate a wide variety of launch vehicle dynamics and control problems at system level since 2001. The backbone of the multibody dynamics simulator is DCAP (Dynamic and Control Analysis Package), a multibody software, developed by ESA together with industry, with more than 30 years heritage in space applications. This software is a suite of fast, effective computer programs that provides the user with capabilities to model, simulate and analyze the dynamics and control performances of coupled rigid and flexible structural systems subjected to possibly time-varying structural characteristics and space environmental loads. The simulator uses the formulation for the dynamics of multi-rigid/flexible-body systems based on Order( n) algorithm. This avoids the explicit computation of a global mass matrix and its inversion, and the computational burden in these schemes increases only linearly with the number n of the system's degrees of freedom. A dedicated symbolic manipulation pre-processor is then used in the coding optimization. With the implementation of dedicated interfaces to other specialised
Overview of recent nuclear analyses for the Upper ECH launcher in ITER
Serikov, A., E-mail: serikov@inr.fzk.d [Association FZK-EURATOM, Forschungszentrum Karlsruhe, P.O. Box 3640, D-76021 Karlsruhe (Germany); Fischer, U.; Grosse, D.; Heidinger, R.; Kleefeldt, K.; Spaeh, P.; Strauss, D.; Vaccaro, A. [Association FZK-EURATOM, Forschungszentrum Karlsruhe, P.O. Box 3640, D-76021 Karlsruhe (Germany)
2010-12-15
An overview is given for the analyses of the nuclear physics characteristics in support of the development of the Electron Cyclotron Heating (ECH) launcher installed in the ITER upper port. The launcher's Quasi-Optical (QO) system of millimeter-wave guides represents a pathway for the neutron streaming which results in radiation loads on the launcher internals, mainly on the front steering (FS) mirrors and neighboring ITER components, in particular the vacuum vessel (VV) and the superconducting magnets surrounding the launcher. The radiation transport calculations were performed with the Monte Carlo code MCNP5 employing the recent MCNP geometry model of ITER called Alite and the FENDL-2.1 nuclear data. A dedicated CAD model of the QO ECH launcher, generated with CATIA V5, was converted at FZK into the MCNP5 geometry representation using the McCad conversion tool. The neutron and photon fluxes and critical nuclear responses, such as nuclear heating, neutron damage, and the helium production rate were calculated in the paper and compared with the ITER nuclear design limits. On the basis of the results obtained from the nuclear analyses, it is concluded that the recent design of the QO ECH launcher satisfies the ITER radiation requirements, and thus, from this point of view, can be operated safely.
顾亚文; 黄磊; 张静
2014-01-01
In order to study impact degree of secondary structure on the linear induction motor, this paper adopted the finite element method to carry out analysis to four kinds of different secondary materials and structures and compared the locked-mover characteristics and mechanical characteristics of four kinds of linear motors. Analysis result shows that the steel-copper plate composite structure is with higher thrust force and smaller normal force under the same electrical load of linear induction motor, which is the best selection of application in linear railway transpor-tation.%为研究直线感应电机特性受次级的影响程度，采用瞬态有限元方法对四种不同次级材料和结构的直线感应电机进行了分析，并对四种直线电机的堵动特性及机械特性进行了对比。分析结果表明，钢铜平板复合结构的直线感应电机在相同电负荷时，具有较大的电磁推力输出和较小的法向力，是应用于直线轨道交通的最佳选择。
Mechanism of plasma ignition in electrothermal-chemical launcher
Yong Jin
2016-04-01
Full Text Available Plasma generator is a core component in an electrothermal-chemical (ETC launcher. Its work state directly influences the launch efficiency of a system. The interaction between plasma and propellants is a very important mechanism in ETC technology. Based on the transient radiation model and open air plasma jet experiment, the mechanism of plasma ignition process is analyzed. Results show that the surface temperature of local solid propellant grain can quickly achieve the ignition temperature under the action of early transient plasma radiation. But it needs enough time to maintain the high energy flow to make self-sustained combustion of solid propellant grains. Because of the limited space characteristics of transient radiation, the near-field propellant grains can gain enough energy by the strong transient radiation to be ignited and achieve self-sustained combustion. The far-field propellant grains mainly gain the energy by the activated particles in plasma jet to be ignited and self-sustained combustion. Experiments show that plasma jet always has a high flow velocity in the area of the cartridge. Compared with conventional ignition, the solid propellant grains can obtain more quick and uniform ignition and self-sustained combustion by this kind of ablation controlled arc (ACA plasma via energy skin effect of propellant grains, pre-heat temperature mechanism and high efficient jet diffusion.
Mechanism of plasma ignition in electrothermal-chemical launcher
Yong JIN; Yan-jie NI; Hai-yuan LI; Bao-ming LI
2016-01-01
Plasma generator is a core component in an electrothermal-chemical (ETC) launcher. Its work state directly influences the launch efficiency of a system. The interaction between plasma and propellants is a very important mechanism in ETC technology. Based on the transient radiation model and open air plasma jet experiment, the mechanism of plasma ignition process is analyzed. Results show that the surface temperature of local solid propellant grain can quickly achieve the ignition temperature under the action of early transient plasma radiation. But it needs enough time to maintain the high energy flow to make self-sustained combustion of solid propellant grains. Because of the limited space characteristics of transient radiation, the near-field propellant grains can gain enough energy by the strong transient radiation to be ignited and achieve self-sustained combustion. The far-field propellant grains mainly gain the energy by the activated particles in plasma jet to be ignited and self-sustained combustion. Experiments show that plasma jet always has a high flow velocity in the area of the cartridge. Compared with conventional ignition, the solid propellant grains can obtain more quick and uniform ignition and self-sustained combustion by this kind of ablation controlled arc (ACA) plasma via energy skin effect of propellant grains, pre-heat temperature mechanism and high efficient jet diffusion.
Acoustic and Vibration Environment for Crew Launch Vehicle Mobile Launcher
Vu, Bruce T.
2007-01-01
A launch-induced acoustic environment represents a dynamic load on the exposed facilities and ground support equipment (GSE) in the form of random pressures fluctuating around the ambient atmospheric pressure. In response to these fluctuating pressures, structural vibrations are generated and transmitted throughout the structure and to the equipment items supported by the structure. Certain equipment items are also excited by the direct acoustic input as well as by the vibration transmitted through the supporting structure. This paper presents the predicted acoustic and vibration environments induced by the launch of the Crew Launch Vehicle (CLV) from Launch Complex (LC) 39. The predicted acoustic environment depicted in this paper was calculated by scaling the statistically processed measured data available from Saturn V launches to the anticipated environment of the CLV launch. The scaling was accomplished by using the 5-segment Solid Rocket Booster (SRB) engine parameters. Derivation of vibration environment for various Mobile Launcher (ML) structures throughout the base and tower was accomplished by scaling the Saturn V vibration environment.
蔡骏; 邓智泉
2012-01-01
Sensorless starting and low speed operation is a difficult research branch in switched reluctance motor （SRM）. In this paper, the three modes such as the standstill, rotating shaft condition and the driving runming condition are considered. A sensorless control method is presented in this paper, which is based on the phase inductance model in linear region. In this method, the phase current slope difference calculation method is utilized for identifying the full-cycle inductance; based on the inductance characteristics, the inductance comparison logics are proposed for estimating the inductance linear region; and in the linear region, the position vs. inductance characteristics are modeled for estimating the rotor position and speed information, which can be used for sensorless starting and driving operation without hesitation. The experimental results verify the theoretical analysis and its validity.%无位置传感器起动和低速运行控制是开关磁阻电机研究的难点问题。分别针对静止、带初始转速，以及驱动运行3种模式进行了研究，提出了一种基于电感线性区模型的开关磁阻电机无位置传感器控制方法。该方法采用电流斜率差值计算法来辨识全周期的电感信息；并通过设计电感比较逻辑实现电感线性区的估计；在电感线性区建立了角度一电感关系的数学模型，可以直接估计出转子位置和转速信息，实现无位置传感器无反转起动和运行控制。实验结果验证了理论分析的正确性和可行性。
王智勇
2014-01-01
Based on the requirement of high-power linear propulsion system, the short-time periodic linear induction motor ( LIM) needs to be designed. Based on thermal network, taking into account the end-winding and the effects of thermal conduction composite materials, the calculation method of the linear induction motor temperature field was proposed. The thermal network model of the temperature field of the periodic transient LIM was deduced. The rule of the LIM coil temperature change was obtained accurately. The simulation model was established based on the mathematical model, and then the performance of the motor thermal dissipation was simulated, which provided an important reference for the design and performance analysis of the linear induction motor.%基于大功率直线推进的要求，设计短时周期工作的直线感应电机。提出了基于热网络法，计及端部绕组热传导、复合材料影响的直线电机温度场计算方法，推导了周期暂态工作的直线电机温度场热网络模型，得到了该直线电机线圈导体准确的温度变化规律。基于数学模型建立了仿真模型，对电机散热性能进行了仿真计算，为该直线感应电动机的设计和性能分析提供了重要参考。
Wave induced density modification in RF sheaths and close to wave launchers
Van Eester, D., E-mail: d.van.eester@fz-juelich.de [Laboratory for Plasma Physics, ERM/KMS, EUROfusion Consortium Member, Brussels (Belgium); Crombé, K. [Laboratory for Plasma Physics, ERM/KMS, EUROfusion Consortium Member, Brussels (Belgium); Department of Applied Physics, Ghent University, Ghent (Belgium); Lu, Ling-Feng [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France)
2015-12-10
With the return to full metal walls - a necessary step towards viable fusion machines - and due to the high power densities of current-day ICRH (Ion Cyclotron Resonance Heating) or RF (radio frequency) antennas, there is ample renewed interest in exploring the reasons for wave-induced sputtering and formation of hot spots. Moreover, there is experimental evidence on various machines that RF waves influence the density profile close to the wave launchers so that waves indirectly influence their own coupling efficiency. The present study presents a return to first principles and describes the wave-particle interaction using a 2-time scale model involving the equation of motion, the continuity equation and the wave equation on each of the time scales. Through the changing density pattern, the fast time scale dynamics is affected by the slow time scale events. In turn, the slow time scale density and flows are modified by the presence of the RF waves through quasilinear terms. Although finite zero order flows are identified, the usual cold plasma dielectric tensor - ignoring such flows - is adopted as a first approximation to describe the wave response to the RF driver. The resulting set of equations is composed of linear and nonlinear equations and is tackled in 1D in the present paper. Whereas the former can be solved using standard numerical techniques, the latter require special handling. At the price of multiple iterations, a simple ’derivative switch-on’ procedure allows to reformulate the nonlinear problem as a sequence of linear problems. Analytical expressions allow a first crude assessment - revealing that the ponderomotive potential plays a role similar to that of the electrostatic potential arising from charge separation - but numerical implementation is required to get a feeling of the full dynamics. A few tentative examples are provided to illustrate the phenomena involved.
Wave induced density modification in RF sheaths and close to wave launchers
Van Eester, D.; Crombé, K.; Lu, Ling-Feng
2015-12-01
With the return to full metal walls - a necessary step towards viable fusion machines - and due to the high power densities of current-day ICRH (Ion Cyclotron Resonance Heating) or RF (radio frequency) antennas, there is ample renewed interest in exploring the reasons for wave-induced sputtering and formation of hot spots. Moreover, there is experimental evidence on various machines that RF waves influence the density profile close to the wave launchers so that waves indirectly influence their own coupling efficiency. The present study presents a return to first principles and describes the wave-particle interaction using a 2-time scale model involving the equation of motion, the continuity equation and the wave equation on each of the time scales. Through the changing density pattern, the fast time scale dynamics is affected by the slow time scale events. In turn, the slow time scale density and flows are modified by the presence of the RF waves through quasilinear terms. Although finite zero order flows are identified, the usual cold plasma dielectric tensor - ignoring such flows - is adopted as a first approximation to describe the wave response to the RF driver. The resulting set of equations is composed of linear and nonlinear equations and is tackled in 1D in the present paper. Whereas the former can be solved using standard numerical techniques, the latter require special handling. At the price of multiple iterations, a simple 'derivative switch-on' procedure allows to reformulate the nonlinear problem as a sequence of linear problems. Analytical expressions allow a first crude assessment - revealing that the ponderomotive potential plays a role similar to that of the electrostatic potential arising from charge separation - but numerical implementation is required to get a feeling of the full dynamics. A few tentative examples are provided to illustrate the phenomena involved.
Mass sensitivity studies for an inductively driven railgun
Scanlon, J.J. (Science Applications International Corp., Marietta, GA (US)); Young, A.F. (Air Force Armament Lab., Eglin AFB, FL (United States))
1991-01-01
One of the primary system constructs for an Electromagnetic Launcher (EML) System consists of a homopolar generator (HPG) driven by a hot hydrogen multi-stage turbine/nuclear reactor. The HPG is used to charge an inductive energy store. A key evaluation criterion for determining the viability of an EML is system mass. The objective of this paper is to identify those areas which result in substantial system mass reductions for an HPG driven EML. Sensitivity studies are performed by varying launch mass peak acceleration, launcher efficiency, inductance gradient (L{prime}), injection velocity, barrel mass per unit length, fuel tankage and pump estimates, and component energy and power densities. Two major contributors to the system mass are the allowed number of shots per barrel versus the number required for the mission, and the barrel length.
李练兵; 王志强; 赵秀峰; 王志华
2013-01-01
针对传统的基于堵转和空转模型计算感应电机参数的离线辨识方法实施困难,甚至不可行的问题,通过线性变换得到一种电机的等效模型,实现了感应电机在静止状态下的参数辨识.%Considering difficulty in off-line identifying induction motor parameter based on traditional locked-rotor idle model calculation, a linear transformation-based equivalent model for motors was proposed to implement parameter identification of the induction motor in stationary state.
Kong, Xiangxi; Zhang, Xueliang; Chen, Xiaozhe; Wen, Bangchun; Wang, Bo
2016-05-01
In this paper, phase and speed synchronization control of four eccentric rotors (ERs) driven by induction motors in a linear vibratory feeder with unknown time-varying load torques is studied. Firstly, the electromechanical coupling model of the linear vibratory feeder is established by associating induction motor's model with the dynamic model of the system, which is a typical under actuated model. According to the characteristics of the linear vibratory feeder, the complex control problem of the under actuated electromechanical coupling model converts to phase and speed synchronization control of four ERs. In order to keep the four ERs operating synchronously with zero phase differences, phase and speed synchronization controllers are designed by employing adaptive sliding mode control (ASMC) algorithm via a modified master-slave structure. The stability of the controllers is proved by Lyapunov stability theorem. The proposed controllers are verified by simulation via Matlab/Simulink program and compared with the conventional sliding mode control (SMC) algorithm. The results show the proposed controllers can reject the time-varying load torques effectively and four ERs can operate synchronously with zero phase differences. Moreover, the control performance is better than the conventional SMC algorithm and the chattering phenomenon is attenuated. Furthermore, the effects of reference speed and parametric perturbations are discussed to show the strong robustness of the proposed controllers. Finally, experiments on a simple vibratory test bench are operated by using the proposed controllers and without control, respectively, to validate the effectiveness of the proposed controllers further.
Zero Boil Off Cryogen Storage for Future Launchers
Valentian, D.; Plachta, D.; Kittel, P.; Hastings, L. J.; Salerno, Louis J.; Arnold, James O. (Technical Monitor)
2001-01-01
Zero boil off (ZBO) cryogen storage using both cryocoolers and passive insulation technologies will enable long-term exploration missions by allowing designers to optimize tankage without the need for excess cryogen storage to account for boil off. Studies of ZBO (zero boil off) have been on-going in the USA for several years. More recently, a review of the needs of advanced space propulsion took place in Europe. This showed the interest of the European community in cryogenic propulsion for planetary missions as well as the use of liquid hydrogen for large power electric propulsion (manned Mars missions). Although natural boiling could be acceptable for single leg missions, passive insulation techniques yield roughly a I% per month cryogen loss and this would not be cost effective for robotic planetary missions involving storage times greater than one year. To make economic sense, long-term exploration missions require lower tank capacity and longer storage times. Recent advances in cryocooler technology, resulting in vast improvements in both cooler efficiency and reliability, make ZBO is a clear choice for planetary exploration missions. Other, more near term applications of ZBO include boil-off reduction or elimination applied to first and upper stages of future earth-to-orbit (ETO) launchers. This would extend launch windows and reduce infrastructure costs. Successors to vehicles like Ariane 5 could greatly benefit by implementing ZBO. Zero Boil Off will only be successful in ETO launcher applications if it makes economic sense to implement. The energy cost is only a fraction of the total cost of buying liquid cryogen, the rest being transportation and other overhead. Because of this, higher boiling point cryogens will benefit more from on-board liquefaction, thus reducing the infrastructure costs. Since hydrogen requires a liquefier with at least a 17% efficiency just to break even from a cost standpoint, one approach for implementing ZBO in upper stages would
Direct reading inductance meter
Kolby, R. B. (Inventor)
1977-01-01
A direct reading inductance meter comprised of a crystal oscillator and an LC tuned oscillator is presented. The oscillators function respectively to generate a reference frequency, f(r), and to generate an initial frequency, f(0), which when mixed produce a difference equal to zero. Upon connecting an inductor of small unknown value in the LC circuit to change its resonant frequency to f(x), a difference frequency (f(r)-f(x)) is produced that is very nearly a linear function of the inductance of the inductor. The difference frequency is measured and displayed on a linear scale in units of inductance.
Design and manufacturing of the ITER ECRH upper launcher mirrors
Sanchez, Francisco [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOMConfederation, Suisse, CH-1015 Lausanne (Switzerland)], E-mail: francisco.sanchez@epfl.ch; Bertizzolo, R.; Chavan, R.; Collazos, A. [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOMConfederation, Suisse, CH-1015 Lausanne (Switzerland); Henderson, M. [ITER Organization, Cadarache Centre, Saint Paul Lez Durance (France); Landis, J.D. [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOMConfederation, Suisse, CH-1015 Lausanne (Switzerland)
2009-06-15
Four of the 16 ITER upper port plugs will be devoted to electron cyclotron resonance heating (ECRH) in order to control magnetohydrodynamic (MHD) instabilities . In order to achieve the stabilisation of the neoclassical tearing modes (NTM) and sawtooth oscillation, a deposition of a very localized and peaked current density profile over a broad poloidal steering range is required. In the present optical configuration eight 2 MW mm-wave beams enter each of the four upper launchers (UL) through waveguides into the vacuum vessel. Each beam line comprises consecutive corrugated waveguide sections with two mitre bends, orientating the poloidal and toroidal directions and three sections of quasi-optical transmission . The beam waist locations and beam shaping properties in free space propagation are defined by two additional mirrors, the first being a static focusing mirror and the second a plane poloidally steerable mirror. Each mirror reflects a group of 4 mm-wave beams. The three types of UL mirrors (mitre bend, focusing and steering) absorb heat generated essentially by three sources: the ohmic loss of the RF beam reflected at the mirror surfaces and the nuclear and thermal radiation coming from the plasma. While the average heat load is within reasonable engineering limits, three elements condition the actual mirror design, the peak ohmic heat load (Gaussian or Bessel type heat deposition profiles), the electromagnetic forces generated in vertical disruption events (VDE), and the ITER cooling water requirements. This paper provides an overview of the different upper port-plug mirror designs and cooling schemes and an outlook on the prototype manufacturing activities and the future test program. The optimized mm-wave layout within the ECH port plugs is also presented.
黄书荣; 徐伟; 胡冬
2015-01-01
Linear induction motors (LIMs) have been widely applied in railway transportation systems in the past thirty years. This is basically due to its merits of simple structure, less energy consumption, less manufacturing cost, etc. However, for the LIMs special characters such as cut-open magnetic circuit and large air gap length, survey on LIM is much more dififcult than traditional rotary motor. This paper brielfy describes merits, four main structures and characters of linear induction motor applied in railway transportation. The paper summarizes research and development of linear induction motor at home and abroad, and discusses several key technology problems.%直线感应电机牵引系统由于结构简单、系统能耗小、造价低等优点，近年来在轨道交通中得到广泛应用。然而直线感应电机因磁路开断、初次级间隙大等特性，其研究比传统感应电机更复杂。文章对轨道交通用直线感应电机牵引系统的优点进行了简要综述，介绍了直线感应电机四种主要结构形式和国内外相关研究进展，探讨了轨道交通用直线感应电机的一些关键技术难题。
单边直线感应电动机直接推力控制方法研究%Research of Direct Thrust Control Method for Single-Sided Linear Induction Motor
易一鹏; 庄圣贤; 周志超; 程远银
2011-01-01
The movement of a short-primary long-secondary single-sided linear induction motor causes eddy currents in the secondary conductor sheet at the entry and the exit of the primary core, resulting in distortion of flux and serious influences on performance of the linear induction motor(LIM).In this paper, an equivalent circuit of the linear induction motor was developed by quantifying its dynamic longitudinal edge effect.Then, simulation models of the LIM with and without consideration of the edge effect were presented, based on the proposed equivalent circuit according to the principle of direct thrust control.By simulation, the suggested scheme is proved to be an effective method for LIMs.%短初级长次级单边直线感应电动机的初级在进入和离开次级导体板时会产生涡流,引起气隙磁场畸变,造成损耗,严重影响电机的运行性能.通过量化体现动态纵向边缘效应的影响,得出直线感应电动机等效电路模型.根据直接转矩控制原理,建立了在不考虑和考虑边缘效应影响下的直线感应电动机直接推力控制系统模型,按照已知参数进行仿真.仿真说明该方法在直线感应电动机控制上取得了良好的控制性能.
Thio, Y.C.
1985-05-01
The second year of a 4-year program to develop an ultra-high velocity electromagnetic launcher has been completed, with significant progress made in the key technical areas. This lays firmly the cornerstone for major progress in Year 3 of the program. The launcher instrumentation and diagnostics system was developed. More than 20 launcher experiments were conducted using the SUVAC-I augmented launcher system. We tested our novel plasma generation technique using a lithium seeded propellant with encouraging success. We accelerated a 1.4 g projectile to 5.3 km/s in 1.6 m in the series. Unaugmented barrels for SUVAC-II were fabricated. The barrels were tested and commissioned with a total of 8 firings in single-stage configurations. The tests verified the basic soundness of the barrel mechanical and electrical design. Velocity up to 4.4 km/s was achieved with a 1.1 g projectile. Concurrently, we completed the fabrication, assembly and installation of SUVAC-II power supply (1 MJ) and its expanded control system. Experimentation with the multi-stage SUVAC-II launcher is expected to take place in the early part of Year 3. In the meantime, fabrication of the SUVAC-III power supply (an additional 0.4 MJ) has also been initiated.
张纪勇
2013-01-01
According to the working principle of a rotary motor developed the cylindrical linear lifting model based on the linear induction motor. And established the equivalent circuit which calculates the model structure sizes and starting characteristic parameters considering the effect of side end from the relationship of energy equilibrium, This will lay on the technical foundation for the practical of the lifting model.% 根据旋转电动机工作原理，研发了基于直线感应电动机的圆筒形直线举升模型，并从能量平衡的角度建立了考虑边端效应的等效电路，计算了模型结构参数和起动特性参数，为举升模型的实用化奠定了技术基础。
卢永芳; 石军亮
2012-01-01
According to the structure of double cylindrical linear inductive motor,and by solving magnetic Geld equations, the starting performance of the linear motor was calculated. In computation, the effects of saturation,eddy current and the end effect were fully taken into account. The agreement of calculated values with test results shows the validity of the present method.%针对双筒复合次级直线感应电动机的结构特点,从场的角度,提出了一种通过对磁场的分析计算,求取电机起动性能的计算方法,该算法充分考虑了起动时边端效应的影响,计算数据与试验结果基本吻合,表明了该计算方法的可行性.
International Space Station-Based Electromagnetic Launcher for Space Science Payloads
Jones, Ross M.
2013-01-01
A method was developed of lowering the cost of planetary exploration missions by using an electromagnetic propulsion/launcher, rather than a chemical-fueled rocket for propulsion. An electromagnetic launcher (EML) based at the International Space Station (ISS) would be used to launch small science payloads to the Moon and near Earth asteroids (NEAs) for the science and exploration missions. An ISS-based electromagnetic launcher could also inject science payloads into orbits around the Earth and perhaps to Mars. The EML would replace rocket technology for certain missions. The EML is a high-energy system that uses electricity rather than propellant to accelerate payloads to high velocities. The most common type of EML is the rail gun. Other types are possible, e.g., a coil gun, also known as a Gauss gun or mass driver. The EML could also "drop" science payloads into the Earth's upper
许金; 马伟明; 鲁军勇; 孙兆龙; 张育兴
2012-01-01
A novel slot-less double-sided long-stator linear induction motor is proposed for the application of Electromagnetic Launch. In this motor, the conventional gullet structure is cancelled, and conductive area of the motor stator windings is enlarged, and then the loss and temperature rise is decreased. Based on the finite element simulation and calculation of electromagnetic field, the saturation characteristics of stator leakage inductance and excitation inductance are obtained, and the calculation methods in nonlinear conditions of the motor are displayed. The comparison of experimental and calculation results verifies the validity and superiority of the proposed calculation methods.%提出了一种应用于电磁发射场合的新型无槽双边长定子直线感应电机，该电机取消了传统电机的齿槽结构，增大了电机定子绕组的导电面积，降低了电机损耗和温升。基于电磁场有限元仿真计算得到了电机定子漏感和励磁电感的饱和特性，给出了电机非线性工况的计算方法。实验结果和计算结果的比较验证了计算方法的正确性。
于雷; 侯勇俊; 聂永广; 郗海华; 刘枭
2009-01-01
Based on the characteristics of cylindrical linear induction motor analyzed the eddy current pwer loss of compound secondary by ANSYS finite Element method. Compared with the analyzed experi-mental data, this finite element method is accurate to calculate the power loss. Using this method, cal-culated and analyzed the power loss of compound secondary with different size. The calculating method and law can be helpful in design and manufacture of the cylindrical linear induction motor.%为了准确计算电机次级参数和电机温升,根据圆筒型直线感应电机的特点,利用有限元软件对大功率圆筒型直线感应电机复合次级进行涡流损耗分析,得出复合次级不同厚度值时的涡流损耗功率.通过有限元分析法和通用解析法计算结果的比较,说明了有限元分析的正确性.计算结果对大功率圆筒型直线感应电机的参数计算与制造有一定的实用价值.
李志宏; 强雄; 计丽霞; 朱岷
2015-01-01
介绍了直线感应电动机的特点及市场应用前景，对其结构和工作原理进行了阐述。通过对样本电机的测试，获得在不同气隙下的输入功率、推力和功率因数等性能数据，分析了磁场气隙调整对直线感应电动机性能的重要影响，为设计、制造和调整不同工况下气隙值的选择提供参考。%The characteristics and market prospect of application of linear induction motor were introduced, the structure and working principle were expounded. Through to the sample motor test, obtained under different air gap of the input power, thrust and power factor and other performance data, analysis of the air gap magnetic field adjustment important influence on the properties of linear induction motor, adjust the under different working conditions for the design, manufacture and provide reference for the selection of the air gap value. gap magnetic field of the analysis and design of experiment.
Research on basic theory high-speed multi-stage cylinder linear induction motor%高速多级圆筒型直线感应电机基础理论研究
关晓存; 雷彬; 李治源; 赵然
2011-01-01
The linear induction motor has small force and speed. So the high-speed multi-stage cylinder linear induction motor (HSMCLIM) was presented, this motor has the characteristics of light weight of mover, simple manufacture process, good force characteristics. Based on electromagnetic field theory, the mathematical model of the motor was deduced, which considers inter-stage coupling effect. The dynamic performance of the motor was simulated, and the variation patterns of voltage, current of stator、 current, speed, acceleration of mover were presented. Simulation result shows that it was feasible to launch a heavy body by this type of linear motor. Experiment results were correspondent with simulation results, they were coincidence well. It verified the validity of the model and provided a new way for the study and implementation of control strategy of this kind of machine.%针对目前直线感应电机推力小,速度低的问题,提出一种高速多级圆筒型直线感应电机,其具有动子质量轻,推力大,加工难度小等优点,特别适于高速发射领域.基于电磁场理论,推导考虑级间耦合的直线感应电机数学模型,用该模型分析电机的动态性能,得到了定子电流、动子速度和加速度等参数变化规律,并进行样机实验,其仿真结果与测量结果进行对比,二者吻合较好.从而为该类电机工程化具体实现提供理论基础.
聂世雄; 孙兆龙; 马伟明; 许金; 熊又星
2016-01-01
Decoupling of normal force and thrust via gap in double-sided linear induction motor is stu-died at first.The multilayer model of double-sided linear induction motor is established according to the multilayer electromagnetic theory.Then normal and tangential magnetic fields are derived.Nor-mal force and thrust are calculated by Maxwell stress tensor method and the curves of electromagnetic force characteristics vs.gap offset and slip are obtained.Simulation combined with motion equations is conducted to find disciplinarian of electromagnetic force characteristics vs.gap offset.An experi-ment is carried out in a high power linear accelerator platform at last.The result shows that the se-condary oscillates in the gap,which conforms to the theory analysis.%首先，采用多层电磁场理论建立了双边直线感应电机的多层简化模型，推导了法向和切向磁场的表达式；然后，运用麦克斯韦应力张量法计算了法向力和水平推力，得到了电磁力的气隙-转差率特性曲线，并结合运动方程进行仿真，分析了法向力和水平推力随气隙偏移变化的规律；最后，利用大功率直线加速平台进行试验验证，试验结果表明：动子在气隙内发生了振荡运动，振荡特征与理论分析吻合较好。
Eduardo Giraldo Suárez
2009-01-01
Full Text Available Este documento presenta la aplicación de la técnica de control no lineal clásica llamada linealización por realimentación de variables de estado. Se hace una aplicación en el motor de inducción, la variable a controlar es la velocidad del eje del motor, el sistema emplea el esquema de control vectorial para máquinas de corriente alterna desarrollado en las últimas décadas; este método es análogo a la técnica de control del motor de corriente directa. El modelo del motor de inducción se describe en el sistema de coordenadas de campo orientado del flujo de rotor y se muestra una introducción al producto y la derivada de Lie, empleados en el diseño del controlador no lineal.This articles shows the application of a classic non-linear control technique called "linearization by feedback of status variables." An application on the induction engine is made. Variable to be controlled is speed of the engine shaft. The system employs a vectorial control scheme for AC engines developed during the last decades. This is a method analogous to the DC engine control technique. Induction engine model is described in the guided field coordinate system of rotor flow. Introduction to the product and Lie derivative used for designing the non-linear controller are shown.
Holakooie, Mohammad Hosein; Ojaghi, Mansour; Taheri, Asghar
2016-01-01
This paper investigates sensorless indirect field oriented control (IFOC) of SLIM with full-order Luenberger observer. The dynamic equations of SLIM are first elaborated to draw full-order Luenberger observer with some simplifying assumption. The observer gain matrix is derived from conventional procedure so that observer poles are proportional to SLIM poles to ensure the stability of system for wide range of linear speed. The operation of observer is significantly impressed by adaptive scheme. A fuzzy logic control (FLC) is proposed as adaptive scheme to estimate linear speed using speed tuning signal. The parameters of FLC are tuned using an off-line method through chaotic optimization algorithm (COA). The performance of the proposed observer is verified by both numerical simulation and real-time hardware-in-the-loop (HIL) implementation. Moreover, a detailed comparative study among proposed and other speed observers is obtained under different operation conditions.
Assessment of the Feasibility of Innovative Reusable Launchers
Chiesa, S.; Corpino, S.; Viola, N.
The demand for getting access to space, in particular to Low Earth Orbit, is increasing and fully reusable launch vehicles (RLVs) are likely to play a key role in the development of future space activities. Up until now this kind of space systems has not been successfully carried out: in fact today only the Space Shuttle, which belongs to the old generation of launchers, is operative and furthermore it is not a fully reusable system. In the nineties many studies regarding advanced transatmospheric planes were started, but no one was accomplished because of the technological problems encountered and the high financial resources required with the corresponding industrial risk. One of the most promising project was the Lockheed Venture Star, which seemed to have serious chances to be carried out. Anyway, if this ever happens, it will take quite a long time thus the operative life of Space Shuttle will have to be extended for the International Space Station support. The purpose of the present work is to assess the feasibility of different kinds of advanced reusable launch vehicles to gain access to space and to meet the requirements of today space flight needs, which are mainly safety and affordability. Single stage to orbit (SSTO), two stage to orbit (TSTO) and the so called "one and a half" stage to orbit vehicles are here taken into account to highlight their advantages and disadvantages. The "one and a half" stage to orbit vehicle takes off and climbs to meet a tanker aircraft to be aerially refuelled and then, after disconnecting from the tanker, it flies to reach the orbit. In this case, apart from the space vehicle, also the tanker aircraft needs a dedicated study to examine the problems related to the refuelling at high subsonic speeds and at a height near the tropopause. Only winged vehicles which take off and land horizontally are considered but different architectural layouts and propulsive configurations are hypothesised. Unlike the Venture Star, which
Graswinckel, M. R.; Bongers, W. A.; M.R. de Baar,; van den Berg, M. A.; Denisov, G.; Donne, A. J. H.; Elzendoorn, B. S. Q.; Goede, A. P. H.; Heidinger, R.; Kuzikov, S.; Kruijt, O. G.; Kruizinga, B.; Moro, A.; Poli, E.; Ronden, D. M. S.; Saibene, G.; Thoen, D. J.; Verhoeven, A. G. A.
2008-01-01
Electron cyclotron current drive will become the main scheme on ITER for the stabilization of neoclassical tearing modes (NTMs) and the control of sawtooth oscillations. The effectiveness of this scheme forms the basis for the requirements of the ITER Upper Port Launcher. These requirements include
Preliminary feasibility assessment for Earth-to-space electromagnetic (Railgun) launchers
Rice, E. E.; Miller, L. A.; Earhart, R. W.
1982-01-01
An Earth to space electromagnetic (railgun) launcher (ESRL) for launching material into space was studied. Potential ESRL applications were identified and initially assessed to formulate preliminary system requirements. The potential applications included nuclear waste disposal in space, Earth orbital applications, deep space probe launchers, atmospheric research, and boost of chemical rockets. The ESRL system concept consisted of two separate railgun launcher tubes (one at 20 deg from the horizontal for Earth orbital missions, the other vertical for solar system escape disposal missions) powered by a common power plant. Each 2040 m launcher tube is surrounded by 10,200 homopolar generator/inductor units to transmit the power to the walls. Projectile masses are 6500 kg for Earth orbital missions and 2055 kg for nuclear waste disposal missions. For the Earth orbital missions, the projectile requires a propulsion system, leaving an estimated payload mass of 650 kg. For the nuclear waste disposal in space mission, the high level waste mass was estimated at 250 kg. This preliminary assessment included technical, environmental, and economic analyses.
Multistage Electromagnetic and Laser Launchers for Affordable, Rapid Access to Space
2011-07-01
shown by a 2D computer-aided design (CAD) assembly in Figure 3-18. The launcher core contained rails made of UNS C11000 ETP copper with a shoulder...structures. The rails (Figure 3-28) were machined from UNS C11000 ETP copper with a shoulder machined at both ends to seat the bore insulators and
R&D activities on RF contacts for the ITER ion cyclotron resonance heating launcher
Hillairet, Julien; Bamber, Rob; Beaumont, Bertrand; Bernard, Jean-Michel; Delaplanche, Jean-Marc; Durodié, Frédéric; Lamalle, Philippe; Lombard, Gilles; Nicholls, Keith; Shannon, Mark; Vulliez, Karl; Cantone, Vincent; Hatchressian, Jean-Claude; Lebourg, Philippe; Martinez, André; Mollard, Patrick; Mouyon, David; Pagano, Marco; Patterlini, Jean-Claude; Soler, Bernard; Thouvenin, Didier; Toulouse, Lionel; Verger, Jean-Marc; Vigne, Terence; Volpe, Robert
2015-01-01
Embedded RF contacts are integrated within the ITER ICRH launcher to allow assembling, sliding and to lower the thermo-mechanical stress. They have to withstand a peak RF current up to 2.5 kA at 55 MHz in steady-state conditions, in the vacuum environment of themachine.The contacts have to sustain a temperature up to 250{\\textdegree}Cduring several days in baking operations and have to be reliable during the whole life of the launcher without degradation. The RF contacts are critical components for the launcher performance and intensive R&D is therefore required, since no RF contactshave so far been qualified at these specifications. In order to test and validate the anticipated RF contacts in operational conditions, CEA has prepared a test platform consisting of a steady-state vacuum pumped RF resonator. In collaboration with ITER Organization and the CYCLE consortium (CYclotronCLuster for Europe), an R&D program has been conducted to develop RF contacts that meet the ITER ICRH launcher specification...
Sudmeijer, K.J.; Wentzel, C.; Lefeber, B.M.; Kloosterman, A.
2002-01-01
In this paper a summary is presented of the technology development in the Netherlands focussed on the design and development of a metallic aerodynamic control surface for the future European reusable launcher. The applied materials are mainly Oxide Dispersion Strengthened (ODS) alloys produced by
Free Transverse Vibration Analysis of an Underwater Launcher Based on Fluid-Structure Interaction
Qingyong Niu; Tianyun Li; Xiang Zhu; Lu Wang
2014-01-01
A pneumatic launcher is theoretically investigated to study its natural transverse vibration in water. Considering the mass effect of the sealing cover, the launcher is simplified as a uniform cantilever beam with a top point mass. By introducing the boundary and continuity conditions into the motion equation, the natural frequency equation and the mode shape function are derived. An iterative calculation method for added mass is also presented using the velocity potential function to account for the mass effect of the fluid on the launcher. The first 2 order natural frequencies and mode shapes are discussed in external flow fields and both external and internal flow fields. The results show good agreement with both natural frequencies and mode shapes between the theoretical analysis and the FEM studies. Also, the added mass is found to decrease with the increase of the mode shape orders of the launcher. And because of the larger added mass in both the external and internal flow fields than that in only the external flow field, the corresponding natural frequencies of the former are relatively smaller.
Effects of engine cycle type on payload delivery of the future European launchers
Manski, D.
It has now been decided that the future European launcher concept is to be the design called Ariane 5P. A two year preparation program has been started in order to determine the final parameters of this launcher and its hydrogen/oxygen HM60 engine. For cost reasons and to avoid risk during the development period, the proposed HM60 engine is based on a modest technology level compared with other modern hydrogen/oxygen engines. A wide range of advanced technology solutions and improvement in the HM60 engine cycle can therefor be used to increase the payload capacity of the future launcher and it is of great interest to investigate this matter in more detail. For this purpose, different analytical models are used, i.e. a mass model, a performance model and a trajectory model. The mass model is split into a structural- and an engine part. Contrary to earlier investigations, the statistical engine mass model is replaced by an analytical one in order to demonstrate the effects caused by different engine cycle types. On this basis, the influence of engine cycle parameters, such as gas generator mixture ratio or turbopump efficiencies, and propulsion parameters such as tank mixture ratio, chamber pressure, nozzle area ratio and thrust level, on payload delivery of different launcher configurations actually under discussion is demonstrated.
Lumped parameter model of double-primary linear induction motor%双初级耦合直线感应电动机集总参数模型
马名中; 马伟明; 张育兴; 王公宝; 李卫超
2012-01-01
在动子进行高速大推力运动场合,直线感应电动机可以设计为N(N≥2)台电机初级绕组上下并联布置共用一个次级的结构形式.本文针对N=2的情形,分析了双初级耦合直线感应电动机上下初级绕组边缘气隙磁场耦合和次级涡流路径耦合关系,在此基础上针对双初级耦合直线感应电动机中双初级上下定子单独通电、双初级同时通入同向电流、双初级同时通入反向电流等不同工况,建立了统一的集总参数模型,并进行了耦合参数的辨识.模型计算和小型试验样机实验结果吻合较好,证明了理论分析的正确性.%In some field where motor secondary needs to get great thrust and high speed, the linear induction motor can be designed to have N (N≥2) primaries sharing only one secondary. For N =2, the edge gas magnetic coupling between up and down primaries in the double-primary linear induction motor was analyzed , and the current wave path coupling on the secondary was studied, based on which, for the different working conditions of double-primary linear induction motor such as only up or down primary works, the up and down stators having in-phase currents or the two stators having reversed currents, the uniform lumped-parameter model was established, and the coupling parameters in the model were identified. The model calculation is in accord with the experiment results, which proves the theoretical analysis is correct.
城轨交通中直线感应牵引电机的效率最优控制%Efficiency optimal control of linear induction motor for urban rail transit
吕刚; 孙守光; 马云双
2009-01-01
Low efficiency of linear induction motor has been studied in the paper, and an efficiency optimail control stratery is proposed. Considering end effect, a math model of linear induction motor was made. Decoupling control of the force and flux was designed, aiming to nolinear and time-variantion of the flux, force and current for linear induction motor. Based on the analyses of the normal force, a primary-current math model was developed. Using optimal theory, we got the least loss function and optimal control.Computer simulations results have been conducted to validate the effectiveness of the proposed control scheme under different reference trajec-tories. The merits of the proposed control system were indicated in comparison with a traditional control system, and simulation results support that the proposed scheme decreased the power loss of the LIM in the cruise period.%针对城市轨道交通中直线感应牵引电机效率较低问题,从控制角度研究电机的效率最优控制策略.建立直线感应牵引电机的数学模型,考虑边缘效应的影响将推力与磁通进行解耦,在分析法向力组成与特性的基础上,得出以初级电流为变量的数学表达式,结合最优化理论,考虑多个优化目标建立损耗最小函数,实现在满足水平推力的条件下对电机铜耗与法向力造成损耗的最优控制.仿真研究对比了采用普通矢量控制与本文所提方案的运行状况.仿真结果表明,直线感应牵引电机行程中恒速区段时间越长,损耗减少得越大,效率提高得越高.
基于直线感应加速器的非相干太赫兹源设计%Design of incoherent THz source based on linear induction accelerator
禹海军; 王少恒; 荆小兵; 蓝朝晖
2013-01-01
太赫兹波的产生途径有很多，本文通过理论设计和数值计算模拟了利用强流直线感应加速器神龙一号来产生 THz波。神龙一号直线感应加速器能够产生最大能量~20 MeV、束流强度~2 kA、脉冲宽度~60 ns 的脉冲电子束，脉冲电子束以不同能量通过偏转半径不相同的偏转磁铁后可以辐射出具有连续频率的太赫兹波。模拟计算了不同能量下的电子束通过偏转半径分别为0.2 m、0.5 m和1 m的偏转磁铁后得到的太赫兹波频率与电子束能量、磁铁偏转半径等的关系，太赫兹波的频率范围可达0.1 THz~9 THz，最大瞬时辐射功率~0.5 W。最后根据神龙一号直线感应加速器漂移段布局，设计得到偏转半径为0.5 m的偏转磁铁结构以及模拟结果。% There are many methods to generate THz wave. The high current linear induction accelerator Dragon-I is used to produce THz wave by applying the theory design and numerical simulation. The Dragon-I linear induction accelerator can produce intense electron beam with current about 2 kA, maximum energy about 20 MeV and pulse width about 60 ns. The intense electron beams which pass through deflection magnet with different radii can synchronously radiate continuous electromagnetic wave in THz frequency. Using the numerical simulation, the electron beams deflected by the magnets with different radii are calculated, and the relation curves among terahertz wave frequency, electron beam energy and radius of deflection are obtained. The frequency range of THz wave can be up to 0.1 THz-9 THz, and the maximum radiated power can achieve 0.5 W. According to the layout of linear induction accelerator, deflection magnet with 0.5 m radius is simulated and designed lastly.
Status of next generation expendable launchers concepts within the FLPP program
Letourneur, Yann; Leleu, Frederic; Pinard, Didier; Krueger, Joerg; Balduccini, Mauro
2010-05-01
In the framework of the preparation of the next generation of launchers to be developed in Europe, the European Space Agency (ESA) has contracted NGL Prime and its industrial team to conduct a first slice of launch system and stage design activities and programmatic analyses for two types of launchers: A new expendable mid-term launch system relying on elements or "Building Blocks" from Ariane and Vega to be operational by 2015. A new long-term launch system called the Next Generation Launcher (NGL) to be operational by 2020-2025. The design reference missions include a 5 metric tons performance requirement into a Geostationary Transfer Orbit (GTO), to meet the European institutional need, with the increased capability to 8 metric tons into GTO by the addition of solid boosters, to meet the commercial market needs. In a first step, a series of trade-offs were conducted to select the concepts that best fit the requirements of the NGL and "Building Block" launcher options, in terms of propulsion (thrust level, engine characteristics), propellant choice (hydrogen, methane or solid propellants), launcher architecture (with or without strap-on boosters, bi or three stages architecture). In a second step, more detailed analyses were carried out in term of thermo-mechanical design, functional architecture, as well as in term of versatility capacity, i.e. the capability of the launcher to perform different missions than the reference ones. Consistently with this technical activity, a programmatic evaluation was consolidated by the industrial team. This paper details the outcomes of the activity carried out during this second step targeting at selecting one or two concepts. The paper will also give an overview and first results of the follow-on contract in which selected NGL concepts are being further investigated, in the prospect of creating a new European launcher family encompassing versions dedicated to the institutional needs and the commercial market (reference
Detection of passing area of no secondary reaction plate for linear induction motor%直线感应电机过无次级感应板区检测
刘可安; 田红旗; 刘勇
2016-01-01
The electromagnetic characteristics of the motor under uncertain electromagnetic induction state were analyzed in order to resolve the problem that there were shocks of the motor current and output thrust for the linear induction motor when passing the area of no secondary reaction plate .Then the change relation of the main inductance with the coupling degree of primary and secondary was obtained . A simulation was conducted and the variation of motor parameters in this process was studied .An adaptive identification algorithm based on full-order state observer for mutual inductance was proposed to judge whether the motor was in this uncertain area or not .The uncertain area was detected effectively and passed smoothly by adjusting the d-q current references in real-time and calculating the motor model precisely . Test on the Guangzhou Metro Line 5 proved the validity of the proposed detection and control algorithm in uncertain electromagnetic induction between primary and secondary condition .With this control strategy , the experimental results show that the linear induction motor can pass the area of no secondary reaction plate smoothly without any shocks of the motor current and thrust .%为解决大功率直线感应电机工程应用中过无次级感应板区域存在的电机电流和推力冲击的问题，详细分析电机非确定电磁感应状态下的电磁特性，得到电机主电感随主、次级耦合程度的变化关系。基于计及动态边端效应的直线电机状态空间方程，提出基于全阶观测器的互感在线辨识算法，依此判定是否运行于非确定电磁感应状态。通过实时调整电机 d-q 轴指令电流的给定和电机模型高精度计算，实现直线电机非确定电磁感应状态的有效检测和平滑过渡。依托广州地铁5号线实际应用项目进行所提直线电机初、次级非确定电磁感应状态下检测和控制算法的实验验证。实验结果表明：该控制策略
磁浮直线电机的分段最大加速度跟踪控制%Maximum Acceleration Tracing Control for the Single-sided Linear Induction Motor
陈特放; 邓江明; 唐建湘; 成庶
2015-01-01
单边直线感应电机(Single-sided Linear Induction Motors，SLIMs)作为中低速磁悬浮列车的驱动装置，其推力和法向力的优良控制特性以及抗干扰能力，对于列车的牵引及悬浮系统稳定高效运行极为重要。通过建立SLIM的最大加速度变电流跟踪控制模型，在加/减速区，控制SLIM以恒定最大加速度运行；在稳速区，为充分利用电机的容量，控制SLIM恒功率运行。实验验证了所提控制算法的有效性，不仅能有效研究SLIM推力特性，还能为探索磁悬浮的高效动态控制方法提供参考。%On the premise of constant slip-frequency, an approach of variant current with maximum acceleration is proposed to achieve high efficiency control of Single-sided Linear Induction Motors (SLIMs). By regulating current, the thrust is kept with positive or negative to minimize time consumption in acceleration or deceleration sections, respectively, and zero value to bring SLIM into constant power running status in stability sections. Validity of the proposed algorithm is verified by experimental results, and this approach may have some implement value in maglev transportation control.
Flux Tracking Control of Induction Motors
LanLin; XiaowuMu; ChunxiaBu
2004-01-01
This paper deals with flux tracking control of induction motors. Firstly,we analyze convergency of non-homogeneous linear time-varying systems and a sufficient condition is given. Finally, the flux regulator of induction motors is discussed.
饶金; 刘德志; 许金; 马伟明; 徐兴华
2014-01-01
To meet the requirement of the high-power linear propulsion system ,this paper designs a novel twelve-phase linear induction motor (LIM ) with double-sided long stators ,and presents its winding construction .On this basis ,a mathematical model of ABC coordinates for this novel motor is derived ,which is used to analyze the asymmetry of the end-winding leakage inductance in the twelve-phase LIM with double-sided long stators ,which is caused by the relative space position of each phase end-winding in the motor ,and compare it with the asymmetry of the end-winding leakage inductance of the multi-phase rotating motor .Thus ,a simulation model of the motor is established .The model is used for calculating the electromagnetic properties of the motor .The simulation results prove that the mathematical model is correct .%基于大功率直线推进的要求，设计了一种新型十二相双边长定子直线感应电动机，介绍了十二相直线感应电动机的绕组结构。在此基础上，推导了十二相双边长定子直线感应电动机的ABC坐标系数学模型，分析了由电机各相端部绕组空间相对位置决定的十二相直线感应电动机端部漏感的不对称规律，并与多相旋转电机端部漏感的规律进行了对比分析；建立了仿真模型，对电机的电磁性能进行了计算。仿真实验证明了该数学模型的正确性。
许金; 马伟明; 鲁军勇; 孙兆龙; 张育兴
2011-01-01
基于电磁发射特殊需求,设计了一种新型四定子双边直线感应电动机,提出了此新型四定子双边直线感应电动机的电磁模型,分析了电机上、下定子在动子上所感应涡流的耦合特性和上、下定子端部相邻绕组的耦合特性,建立了这种新型直线感应电动机的耦合等效电路模型。基于等效电路模型,分析了上、下定子以及动子上、下等效绕组相关物理量的耦合性质与电机工况间的关系,研究了动子上、下等效绕组相关物理量在数学上实现解耦的工况条件。实验结果验证了所做研究分析的正确性。%A novel double-sided linear induction motor with four stators for the applications of electromagnetic aircraft launch is designed in this paper.The electromagnetic model for this novel motor is proposed,and the coupling characteristics of inductive eddy current of upper and lower stators on shuttles and adjacent end windings of upper and lower stators are analyzed in detail.Based on that,an advanced coupling equivalent circuit model is built for the novel linear induction motor.And based on the advanced coupling equivalent circuit model,the coupling characteristics of relevant physical quantities of the upper and lower stator and upper and lower equivalent windings of shuttle are analyzed.Furthermore,the relationships between the coupling characteristics and motor operation conditions are analyzed,and the operation conditions for mathematical decoupling of relevant physical quantities of shuttle upper and lower equivalent windings are studied.Finally,the experimental results and theoretical derivation results verify the validity and superiority of the proposed design and analysis methods.
蒋映; 石景波
2016-01-01
为了提高长初级直线感应电机的效率，节约电能，在实际应用中需要将其初级分段。以分段长初级直线感应电机为研究对象，采用有限元方法，建立了电机的电磁场计算模型，同时运用虚功法来计算电机的电磁力。通过ANSOFT仿真，研究了电机的空载启动、运行及堵转过程，得出了电机的推力、位移、速度曲线及电机内部电磁场的分布特点。最后，利用 Maxwell2 D软件的有限元法分析了长初级直线感应电机起动推力随气隙大小、分段间距以及启动位置的变化规律。所得到的计算方法与规律对分段长初级直线感应电机的优化设计和制造能提供有益帮助。%The significance is increasing efficiency and saving energy for segmenting the long primary linear motor into blocks.As the research obj ect,the electromagnetic calculation model of the segmented long primary linear induction motor is established by using the finite element method (FEM),and the electromagnetic force computation of the motor is then derived from the virtual work method.The starting,operating and stalling process have been studied by ANSOFT,and the thrust,position and velocity curve are obtained coupled with the electromagnetic field distribution inside the motor.Finally,the change tendency of starting thrust is analyzed by using the FEM of Maxwell 2D,which is along with the variation of the air gap size,the interval of the primary and the starting position.The obtained calculation method can provide useful help for the optimal design and manufacture of the segmented long primary linear induction motor.
方进; 申政
2013-01-01
高温超导直线感应电机对于城市轨道交通的发展具有重要意义.参考常规铜绕组直线感应电机的设计理论,对高温超导直线感应电机进行设计.结合高温超导带材的特性,设计超导绕组线圈的结构并选择单层整距集中绕组结构的方式对线圈在初级铁芯上进行排列,采用无磁材料制作薄壁杜瓦,最后将各个部分整体组装成高温超导直线感应电机试验样机.运用有限元分析软件ANSOFT对所设计的电机建模并进行仿真计算.制作铜绕组试制样机并搭建直线电机牵引测试平台对制作的电机样机进行测试,将试验结果和仿真结果进行对比分析,验证设计的合理性与可行性.%High temperature superconducting linear induction motor (HTS LIM) is significant for the development of urban rail transit.The HTS LIM was designed,using design theory of conventional copper windings linear induction motor as a reference.Combined with the properties of high temperature superconducting tapes,the structure of the superconducting coils was designed and the coils were arranged adopting the single layer concentrated structure in the primary core.The Dewar was manufactured by adopting non magnetic material.Finally,various parts were assembled into HTS LIM test prototype.The model of HTS LIM was built and the simulation was executed by finite element analysis software ANSOFT.The copper windings trial prototype was manufactured and the linear motor traction test platform was set up to test the performance of the motor prototype testing.The test results and simulation results were analyzed to verify the rationality and feasibility of the design.
一种高精确度N相直线电机电感与磁力特性%Inductance and magnetic force analysis of a high-presion N-phase linear motor
蒋浩; 周赣; 黄学良; 张文春
2012-01-01
To meet the motor design optimization and control requirements, a precise mathematical model of N-phase high-precision linear motor is established. According to the periodic distribution of the stator current layer and the rotor permanent magnet layer, the Fourier series method and the magnetic boundary value equations were used to solve the two-dimensional analytical formula of the magnetic field. Then the change trends of the magnetic field with the values of phase N, the height of air gap and current layer were analyzed. The analytic formulas of magnetic flux and magnetic linkage were derived from magnetic field integral of the stator distributed windings; thus the stator winding inductance and its characteristics were obtained, and then the harmonic inductances of a prototype linear motor were analyzed as an example. The virtual current that represented the permanent magnet was proposed and an improved co-energy method was used to calculate the magnetic force pulse. Simulation results indicate the magnetic field is almost sinusoidal, and the harmonic force pulse is approximately zero. The errors of simulation and analytical results are less than 5% , and thus lay the theoretical foundation for the design optimization and real-time control of this type of linear motor.%为了设计一种N相高精确度直线电机,对电机定子和动子磁场分布、电感与磁力特性进行研究.根据定子电流层和动子永磁层的周期性分布特点,运用傅里叶级数方法得到磁场二维解析式.在此基础上,计算磁场随N值、气隙高度、电流层高度的变化趋势.通过对定子分布绕组的磁场进行积分,从而获得电感解析式,并以样机为例分析各次谐波电感特性.提出永磁阵列虚拟电流概念,结合改进的磁共能法计算出各次磁力脉动值.仿真结果表明:当气隙大于1 mm时,定子与动子磁场基本呈正弦分布,高次谐波电感与磁力脉动可忽略,仿真结
Moro, A; Alessi, E; Artaserse, G; Bin, W; Boncagni, L; Bruschi, A; Cirant, S; D’Antona, G; D’Arcangelo, O; Davoudi, M; Farina, D; Ferrero, R; Figini, L; Galperti, C; Garavaglia, S; Granucci, G; Grosso, G; Mellera, V; Minelli, D; Muzzini, V; Nardone, A; Nowak, S; Ramogida, G; Simonetto, A; Sozzi, C
2012-01-01
.... The launcher scheme is based on a two module system, symmetric with respect to the equatorial plane of FTU, with a front steering concept and the launched beams are real-time controllable both...
Bracalente, Candelaria; Ibañez, Irene L. [Departamento de Micro y Nanotecnología, Comisión Nacional de Energía Atómica, San Martín, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires (Argentina); Molinari, Beatriz [Departamento de Radiobiología, Comisión Nacional de Energía Atómica, San Martín, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires (Argentina); Palmieri, Mónica [Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires (Argentina); Kreiner, Andrés [Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires (Argentina); Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica, San Martín, Buenos Aires (Argentina); Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, San Martín, Buenos Aires (Argentina); Valda, Alejandro [Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, San Martín, Buenos Aires (Argentina); and others
2013-11-15
Purpose: To evaluate the cell response to DNA double-strand breaks induced by low and high linear energy transfer (LET) radiations when the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs), an essential protein of the nonhomologous end-joining repair pathway, lacks kinase activity. Methods and Materials: CHO10B2, a Chinese hamster ovary cell line, and its derived radiosensitive mutant cell line, irs-20, lacking DNA-PKcs activity, were evaluated after 0 to 3 Gy of γ-rays, plateau and Bragg peak protons, and lithium beams by clonogenic assay, and as a measurement of double-strand breaks, phosphorylated H2AX (γH2AX) foci number and size were quantified by immunocytofluorescence. Results: Irs-20 exhibited greater radiosensitivity and a higher amount of γH2AX foci than CHO10B2 at 6 hours after irradiation for all types of radiations. Remarkably, CHO10B2 and irs-20 maintained their difference in radiosensitivity after high-LET radiation. Six hours after low-LET radiations, irs-20 did not reach basal levels of γH2AX at high doses, whereas CHO10B2 recovered basal levels for all doses. After high-LET radiation, only CHO10B2 exhibited a reduction in γH2AX foci, but it never reached basal levels. Persistent foci in irs-20 confirmed a repair deficiency. Interestingly, after 30 minutes of high-LET radiation both cell lines exhibited large foci (size >0.9 μm{sup 2}) related to the damage nature, whereas at 6 hours irs-20 showed a higher amount of large foci than CHO10B2, with a 7-fold increase at 3 Gy, that could also be associated to radiosensitivity. Conclusions: We demonstrated, for the first time, an association between deficient DNA-PKcs activity and not only high levels of H2AX phosphorylation but also persistence and size increase of γH2AX foci after high-LET irradiation.
2007-06-01
quickly was necessary. A railgun shot typically occurs in less than 10 ms, and firing capacitor banks to shape the current pulse are in the 100s of...DESIGN OF A COMPUTER-BASED CONTROL SYSTEM USING LABVIEW FOR THE NEMESYS ELECTROMAGNETIC LAUNCHER FACILITY∗ B. M. Huhmanξ 1, J. M. Neri Plasma...has assembled a facility to develop and test materials for the study of barrel lifetime in electromagnetic launchers (EML) for surface-fire support
A projectile-oriented, design study for a cannon-caliber electromagnetic launcher
Zielinski, Alexander E.
1993-01-01
In the design of an efficient gun system the terminal performance must be considered in conjunction with the required input energy. Power conversion for EM acceleration can involve an arduous assessment of numerous, complex components. Results for integrating a finned-rod with a solid armature are here presented. An evaluation is conducted for a rod-projectile launched from a 23 mm, round-bore augmented railgun. We evaluate the projectile design by considering launch, flight, and terminal effects. Four capacitor-based pulsed power supply systems are considered for the launcher. The host vehicle weight limit and largest number of projectiles stowed provide guidance in selecting the optimum configuration. System weight is estimated. Simple scaling for power components is provided to further appraise launcher feasibility. Projectile effectiveness is evaluated at the target using a weapons simulation code and a similar-caliber, conventionally launched projectile.
Angry Birds realized: water balloon launcher for teaching projectile motion with drag
Edwards, Boyd F.; Sam, David D.; Christiansen, Michael A.; Booth, William A.; Jessup, Leslie O.
2014-05-01
A simple, collapsible design for a large water balloon slingshot launcher features a fully adjustable initial velocity vector and a balanced launch platform. The design facilitates quantitative explorations of the dependence of the balloon range and time of flight on the initial speed, launch angle, and projectile mass, in an environment where quadratic air drag is important. Presented are theory and experiments that characterize this drag, and theory and experiments that characterize the nonlinear elastic energy and hysteresis of the latex tubing used in the slingshot. The experiments can be carried out with inexpensive and readily available tools and materials. The launcher provides an engaging way to teach projectile motion and elastic energy to students of a wide variety of ages.
A DYNAMIC MODEL FOR ROCKET LAUNCHER WITH COUPLED RIGID AND FLEXIBLW MOTION
ZHANG Ding-guo; XIAO Jian-qiang
2005-01-01
The dynamics of a coupled rigid-flexible rocket launcher is reported. The coupled rigid-flexible rocket launcher is divided into two subsystems, one is a system of rigid bodies,the other a flexible launch tube which can undergo large overall motions spatially. First, the mathematical models for these two subsystems were established respectively. Then the dynamic model for the whole system was obtained by considering the coupling effect between these two subsystems. The approach, which divides a complex system into several simple subsystems first and then obtains the dynamic model for the whole system via combining the existing dynamic models for simple subsystems, can make the modeling procedure efficient and convenient.
Hachay, O. A.; Khachay, O. Y.; Klimko, V. K.; Shipeev, O. V.
2012-04-01
Geological medium is an open dynamical system, which is influenced on different scales by natural and man-made impacts, which change the medium state and lead as a result to a complicated many ranked hierarchic evolution. That is the subject of geo synergetics. Paradigm of physical mesomechanics, which was advanced by academician Panin V.E. and his scientific school, which includes the synergetic approach is a constructive method for research and changing the state of heterogenic materials [1]. That result had been obtained on specimens of different materials. In our results of research of no stationary geological medium in a frame of natural experiments in real rock massifs, which are under high man-made influence it was shown, that the state dynamics can be revealed with use synergetics in hierarchic medium. Active and passive geophysical monitoring plays a very important role for research of the state of dynamical geological systems. It can be achieved by use electromagnetic and seismic fields. Our experience of that research showed the changing of the system state reveals on the space scales and times in the parameters, which are linked with the peculiarities of the medium of the second or higher ranks [2-5]. Results of seismological and electromagnetic information showed the mutual additional information on different space-time levels of rock massive state, which are energetic influenced by explosions, used in mining technology. It is revealed a change of nonlinearity degree in time of the massive state by active influence on it. The description of massive movement in a frame of linear dynamical system does not satisfy the practical situation. The received results are of great significance because for the first time we could find the coincidences with the mathematical theory of open systems and experimental natural results with very complicated structure. On that base we developed a new processing method for the seismological information which can be used in
Risk mitigation strategy for the ITER electron cyclotron upper port launcher
Goede, A. P. H.; Bongers, W. A.; Elzendoorn, B. S. Q.; Graswinckel, M. F.; M.R. de Baar
2010-01-01
A basic requirement for ITER equipment to meet is a high level of reliability, because ITER operation time is precious and radioactive operation leaves limited scope for repair. In order to reduce the risk of failure during ITER operation an effective risk mitigation strategy is necessary. This paper presents such strategy for the ITER electron cyclotron upper port launcher (ECUPL). A preliminary ECUPL risk analysis identifies possible failure modes. A probabilistic risk assessment quantifies...
Nano-Launcher Technologies, Approaches, and Life Cycle Assessment. Phase II
Zapata, Edgar
2014-01-01
Assist in understanding NASA technology and investment approaches, and other driving factors, necessary for enabling dedicated nano-launchers by industry at a cost and flight rate that (1) could support and be supported by an emerging nano-satellite market and (2) would benefit NASAs needs. Develop life-cycle cost, performance and other NASA analysis tools or models required to understand issues, drivers and challenges.
Stover, Steven; Diebler, Corey; Frazier, Wayne
2006-01-01
The NASA KSC VAB was built to process Apollo launchers in the 1960's, and later adapted to process Space Shuttles. The VAB has served as a place to assemble solid rocket motors (5RM) and mate them to the vehicle's external fuel tank and Orbiter before rollout to the launch pad. As Space Shuttle is phased out, and new launchers are developed, the VAB may again be adapted to process these new launchers. Current launch vehicle designs call for continued and perhaps increased use of SRM segments; hence, the safe separation distances are in the process of being re-calculated. Cognizant NASA personnel and the solid rocket contractor have revisited the above VAB QD considerations and suggest that it may be revised to allow a greater number of motor segments within the VAB. This revision assumes that an inadvertent ignition of one SRM stack in its High Bay need not cause immediate and complete involvement of boosters that are part of a vehicle in adjacent High Bay. To support this assumption, NASA and contractor personnel proposed a strawman test approach for obtaining subscale data that may be used to develop phenomenological insight and to develop confidence in an analysis model for later use on full-scale situations. A team of subject matter experts in safety and siting of propellants and explosives were assembled to review the subscale test approach and provide options to NASA. Upon deliberations regarding the various options, the team arrived at some preliminary recommendations for NASA.
Optimized use of superconducting magnetic energy storage for electromagnetic rail launcher powering
Badel, Arnaud; Tixador, Pascal; Arniet, Michel
2012-01-01
Electromagnetic rail launchers (EMRLs) require very high currents, from hundreds of kA to several MA. They are usually powered by capacitors. The use of superconducting magnetic energy storage (SMES) in the supply chain of an EMRL is investigated, as an energy buffer and as direct powering source. Simulations of direct powering are conducted to quantify the benefits of this method in terms of required primary energy. In order to enhance further the benefits of SMES powering, a novel integration concept is proposed, the superconducting self-supplied electromagnetic launcher (S3EL). In the S3EL, the SMES is used as a power supply for the EMRL but its coil serves also as an additional source of magnetic flux density, in order to increase the thrust (or reduce the required current for a given thrust). Optimization principles for this new concept are presented. Simulations based on the characteristics of an existing launcher demonstrate that the required current could be reduced by a factor of seven. Realizing such devices with HTS cables should be possible in the near future, especially if the S3EL concept is used in combination with the XRAM principle, allowing current multiplication.
Propulsive jet simulation with air and helium in launcher wake flows
Stephan, Sören; Radespiel, Rolf
2016-12-01
The influence on the turbulent wake of a generic space launcher model due to the presence of an under-expanded jet is investigated experimentally. Wake flow phenomena represent a significant source of uncertainties in the design of a space launcher. Especially critical are dynamic loads on the structure. The wake flow is investigated at supersonic (M=2.9 ) and hypersonic (M=5.9 ) flow regimes. The jet flow is simulated using air and helium as working gas. Due to the lower molar mass of helium, higher jet velocities are realized, and therefore, velocity ratios similar to space launchers can be simulated. The degree of under-expansion of the jet is moderate for the supersonic case (p_e/p_∞ ≈ 5 ) and high for the hypersonic case (p_e/p_∞ ≈ 90 ). The flow topology is described by Schlieren visualization and mean-pressure measurements. Unsteady pressure measurements are performed to describe the dynamic wake flow. The influences of the under-expanded jet and different jet velocities are reported. On the base fluctuations at a Strouhal number, around St_D ≈ 0.25 dominate for supersonic free-stream flows. With air jet, a fluctuation-level increase on the base is observed for Strouhal numbers above St_D ≈ 0.75 in hypersonic flow regime. With helium jet, distinct peaks at higher frequencies are found. This is attributed to the interactions of wake flow and jet.
张育兴; 马伟明; 陈伯义; 张明元
2012-01-01
采用合理的等效原则，将电机定子的铁心和绝缘层视为一种等效材料，从一维瞬态温度场模型出发，研究了周期脉冲式直线电机定子温度的变化规律，分析了影响其温度衰减时间常数的主要因素；利用瞬态温度场模型的解析结果，提出了瞬态热网络模型结点数目的确定方法，通过该热网络模型能够快速预测定子温度的变化；研究了温度变化对线圈损耗的影响，并利用实验数据验证了计算模型的正确性，为周期脉冲式电机定子温度的分析计算提供了一种简化有效方法。%The motor stator iron core and insulation layer were regarded as a kind of equivalent material by means of the reasonable equivalent principle. Starting from the 1-D transient temperature field model, the variation law of temperature in a periodic pulse-type linear induction motor stator was studied. The main factors that had an effect on the time constant of the stator temperature attenuation were analyzed. The determination method about the node number of the transient thermal network model was put forward with the use of the analytic results of the transient temperature field model. The variation of the stator temperature could be quickly predicted through the transient thermal network model. The effect of the temperature variation on the coil loss was considered, and the correction of the calculation model was verified through the test data. This paper may provide a valid simple method for the analysis and calculation of temperature in the periodic pulse-type linear induction motor stator.
邓江明; 陈特放; 唐建湘; 张桂新; 余明杨
2012-01-01
Single-sided linear induction motors (SLIMs), with short-primary long-secondary structure, have been broadly used in the intermediate speed range maglev traction drivers. Some parameters of SLIM parameters are nonlinear time-varying greatly for the reason that the equivalent circuit models, considering the end-effect, are asymmetrical. And the traditional speed sensorless methods implied in rotate-motors are invalid or unreliable. This paper first analyzed the M/T equivalent circuits of SLIM and selected the secondary flux as speed observation status variable. From requirements of Lyapunov principal for a stable system, it deduced the speed sensorless identification function suitable for SLIM. Then a feedback-type general integrator observer was used to control the pulse vibration double amplitudes of stable speed. With the estimated speed, it adopted a virtual desired variable (VDV) method to achieve constant sliding frequency vector control of maglev SLIM. The effectiveness of the proposed algorithm is verified through the simulated and experimental results.%单边短初级长次级直线感应电机已普遍应用于低速磁悬浮的驱动系统.由于在动态纵向边端效应影响下等效电路不对称,单边直线感应电机(single-sided linear induction motor,SLIM)的一些参数非线性变化.传统的应用于旋转电机的无速度传感器方法不再适用.首先分析了SLIM的M/T轴等效电路,选择次级磁链作为速度观测器状态变量.根据李雅普诺夫系统稳定性判据,推导出适用于SLIM的无速度传感器辨识；然后,采用反馈广义积分观测器控制稳态辨识速度的双幅脉振幅值；引入虚拟期望变量(virtual desired variable,VDV)法,利用估算速度参与SLIM的恒滑差频率矢量控制.仿真与实验对所提控制算法的有效性和实用性进行了验证,所得结论可为磁悬浮的无速度传感器控制提供参考.
长初级直线感应电机分段供电切换暂态过程%Switch transient process of section powered long-primary linear induction motor
马名中; 马伟明; 范慧丽; 黄垂兵; 李文禄
2015-01-01
In long-primary linear induction motor ( LPLIM) which is section powered with traditional power supply, the movement of the secondary changes the length it overlaps with every section of the primary, which leads to results that the motor parameters vary and the load can' t be precisely controlled. In order to solve this question, a power supply network with intermediate bus was designed, which made the model and parameters of the motor fix in the entire process and guaranteed various control methods to realize high per-formance. In the light of anti-parallel thyristors as the sectional power supply switch, the "Mathematical-Physical" models of a thyristor turn-on and turn-off process were established. The transient process and its influence of the transfer switches used in section powered linear induction motor were analyzed. A section powered two-primary LPLIM prototype was applied to experiment. The experimental results tally with the analytical value, which verified the correctness of the theoretical analysis.%针对采用常规分段供电方式的长初级直线感应电机由于次级的运动,其覆盖每段定子的长度不断变化,导致通电定子段电机参数不断变化,无法对负载实现精确控制的缺点,设计了带中间母排结构的分段供电网络,可以保证电机在整个运行过程中模型和参数固定不变,能够利用现有各种控制算法实现高性能控制. 对于采用反并联晶闸管作为分段供电切换开关,从晶闸管开通和关断的"数学——物理"模型出发,分析了分段供电切换过程中开关暂态过程及其对电机性能的影响. 利用某采用分段供电的长初级双边直线感应电动机原理样机进行实验,实验结果与理论分析相吻合,验证了理论分析的正确性.
Hayes, Brett K; Heit, Evan; Swendsen, Haruka
2010-03-01
Inductive reasoning entails using existing knowledge or observations to make predictions about novel cases. We review recent findings in research on category-based induction as well as theoretical models of these results, including similarity-based models, connectionist networks, an account based on relevance theory, Bayesian models, and other mathematical models. A number of touchstone empirical phenomena that involve taxonomic similarity are described. We also examine phenomena involving more complex background knowledge about premises and conclusions of inductive arguments and the properties referenced. Earlier models are shown to give a good account of similarity-based phenomena but not knowledge-based phenomena. Recent models that aim to account for both similarity-based and knowledge-based phenomena are reviewed and evaluated. Among the most important new directions in induction research are a focus on induction with uncertain premise categories, the modeling of the relationship between inductive and deductive reasoning, and examination of the neural substrates of induction. A common theme in both the well-established and emerging lines of induction research is the need to develop well-articulated and empirically testable formal models of induction. Copyright © 2010 John Wiley & Sons, Ltd. For further resources related to this article, please visit the WIREs website.
冯尚明; 杨波
2009-01-01
A speed estimation method of linear induction motor(LIM) using a novel extended kalman filter(EKF) was presented in this paper. The modification for dynamic end effect of LIM was designed to achieve exact estimation results when LIM ran at high speed. A new approach of optimizing the performance of the extended kalman filter using simulated annealing genetic algorithm (SAGA) was compared with the use of a genetic algorithm(GA). The optimization techniques are verified effective by simulation on a field-oriented controller under various operating conditions including motor parame-ter sensitivity and load disturbance.%采用一种新颖的扩展卡尔曼滤波器(EKF)实现了对直线感应电动机的速度检测,并考虑边端效应的影响进行了修正.采用模拟退火遗传算法(SAGA)对EKF性能进行优化,并与遗传算法(GA)优化的EKF进行了比较,表明SAGA具有更强的寻优能力.包括电机参数变化、负载扰动等情况下的仿真结果证明了该方案的有效性.
贾宏新; 叶云岳; 林瑞光
2001-01-01
This paper introduces a new algorthm for global optimization,theDomain Elimination Algorithm (DEA),into the optimum design of motor.The MULT-SUMT method is combined with improved POWELL method to conduct local optimization procedure.The optimization project is used in the design of linear induction motor.The result is satisfied and can be available in a short time.%把一种新型全局优化算法—区域消去法引进到电机的优化设计中，并针对电机优化问题的具体特点，提出将混合罚函数法和修正的鲍威尔法用于其中的局部寻优。应用该算法对直线电机进行优化设计，较大提高了直线电机的力能指标，且具有收敛速度快的特点。
禹海军; 朱隽; 江孝国; 王远; 陈楠; 张振涛; 戴文华; 刘承俊
2011-01-01
The electron beam generated by the Dragon- I linear induction accelerator strikes the bremsstrahlung converter target to generate X-ray and causes tantalum target damage and hydrodynamic expansion, which results in target density decreasing for successive pulses.The time varying target density was measured by applying a low energy X-ray with energy about 450 kev and spot diameter of 1 to 4 mm along with an intensified charge coupled derice(ICCD) camera.The experiment results show that the target density is basically unchanged for 1 μs after beam-target interaction, and no particle ejected from the front side of the target is found at the same time.%利用能量约450 keV、焦斑直径1～4 mm的低能X光对神龙一号直线感应加速器束靶作用后钽靶的破坏进行诊断,利用增强型电荷耦合器件(ICCD)对诊断过程记录,得到束靶作用后数μs时间内钽靶材料密度的变化.结果表明:在束靶作用后约1μs内靶材料密度基本没有变化,且该时间段内ICCD相机没有观察到有靶前钽靶材料的微粒喷射.
Boncagni, L. [Associazione EURATOM-ENEA sulla Fusione – ENEA, Via Enrico Fermi, 45 00045 Frascati (RM) (Italy); Centioli, C., E-mail: cristina.centioli@enea.it [Associazione EURATOM-ENEA sulla Fusione – ENEA, Via Enrico Fermi, 45 00045 Frascati (RM) (Italy); Galperti, C.; Alessi, E.; Granucci, G. [Associazione EURATOM-ENEA-CNR sulla Fusione – IFP-CNR, Via Roberto Cozzi, 53 20125 Milano (Italy); Grosso, L.A. [Associazione EURATOM-ENEA sulla Fusione – ENEA, Via Enrico Fermi, 45 00045 Frascati (RM) (Italy); Marchetto, C. [Associazione EURATOM-ENEA-CNR sulla Fusione – IFP-CNR, Via Roberto Cozzi, 53 20125 Milano (Italy); Napolitano, M. [Associazione EURATOM-ENEA sulla Fusione – ENEA, Via Enrico Fermi, 45 00045 Frascati (RM) (Italy); Nowak, S. [Associazione EURATOM-ENEA-CNR sulla Fusione – IFP-CNR, Via Roberto Cozzi, 53 20125 Milano (Italy); Panella, M. [Associazione EURATOM-ENEA sulla Fusione – ENEA, Via Enrico Fermi, 45 00045 Frascati (RM) (Italy); Sozzi, C. [Associazione EURATOM-ENEA-CNR sulla Fusione – IFP-CNR, Via Roberto Cozzi, 53 20125 Milano (Italy); Tilia, B.; Vitale, V. [Associazione EURATOM-ENEA sulla Fusione – ENEA, Via Enrico Fermi, 45 00045 Frascati (RM) (Italy)
2013-10-15
Highlights: ► The integration of a new ECRH launcher to FTU legacy control system is reported. ► Fast control has been developed with a three-node RT cluster within MARTe framework. ► Slow control was implemented with a Simatic S7 PLC and an EPICS IOC-CA application. ► The first results have assessed the feasibility of the launcher control architecture. -- Abstract: The role of high power electron cyclotron (EC) waves in controlling magnetohydrodynamic (MHD) instabilities in tokamaks has been assessed in several experiments, exploiting the physical effects induced by resonant heating and current drive. Recently a new EC launcher, whose main goal is controlling tearing modes and possibly preventing their onset, is being implemented on FTU. So far most of the components of the launcher control strategy have been realized and successfully tested on plasma experiments. Nevertheless the operations of the new launcher must be completely integrated into the existing one, and to FTU control system. This work deals with this final step, proposing a hardware and software architecture implementing up to date technologies, to achieve a modular and effective control strategy well integrated into a legacy system. The slow control system of the new EC launcher is based on a Siemens S7 Programmable Logic Controller (PLC), integrated into FTU control system supervisor through an EPICS input output controller (IOC) and an in-house developed Channel Access client application creating an abstraction layer that decouples the IOC and the PLC from the FTU Supervisor software. This architecture could enable a smooth migration to an EPICS-only supervisory control system. The real time component of the control system is based on the open source MARTe framework relying on a Linux real time cluster, devoted to the detection of MHD instabilities and the calculation of the injection angles and the time reference for the radiofrequency power enable commands for the EC launcher.
High Speed Linear Induction Motor Efficiency Optimization
2005-06-01
rotor d. 2 heightrotor ae + overhang length scon p-r length~~ 0 .5 7eto siemens .85 cru=5. 7-10 7 ___ se esc l:-z2.-17 siemens width: 100ikn 3.5 N:= 3...Vsnhs1482 Fp ot( slip1 ot) I K_______iplo)slppo speed ( slippiot) Vsych’ I~ nx sip (lipot 7t 2.106 1.5-.10 6 _ F~l0(s 5-100~ 5 50~ 0.9 0.8 0.7 0.6 0.5
王强; 赵海龙; 代志勇; 孙文遂; 谢龙; 王文斗
2013-01-01
The beam transport system of the Dragon-I linear induction accelerator(LIA) consists of hundreds of solenoid coils and dipole steering coils, which are designed to reduce corkscrew amplitude and transverse motion of electron beam. In order to improve the beam quality, a genetic optimization model of solenoid currents is proposed in this paper and the optimization code GABC based on genetic algorithm and beam transport models is designed, which contains both beam centroid track and the beam envelope model. The matched magnetic field in five blocks of the Dragon- I LIA, including twenty induction acceleration cells and five connection cells, are analyzed using the optimization code. The numerical results reveal that the GABC is effective to solve transport magnetic field optimization problems and could play an important role for beam tuning simulation and experiment.%以直线感应加速器(LIA)匹配磁场设计和束线调谐为背景,提出解决强流相对论电子束长距离、小波动、多元件磁约束的输运优化问题的数值优化办法,建立基于遗传算法的优化程序.结合束质心轨迹及束包络耦合模型,设计描述束传输半径波动大小的评价函数,采用励磁元件馈入电流为优化对象,解决LIA磁场配置“组合爆炸”优化问题.计算结果表明:优化程序可依据不同的初始束流,有针对性地快速给出一组符合束输运要求的励磁电流配置.研究成果为在建的LIA装置束线调谐提供一种重要的数值分析工具.
吴信东
1993-01-01
Machine learning(ML)is a major subfield of artificial intelligence(AI).It has been seen as a feasible way of avoiding the knowledge bottleneck problem in knowledge-based systems development.Research on ML has concentrated in the main on inductive learning,a paradigm for inducing rules from unordered sets of exmaples.AQ11 and ID3,the two most widespred algorithms in ML,are both inductive.This paper first summarizes AQ11,ID3 and the newly-developed extension matrix approach based HCV algorithm;and then reviews the recent development of inductive learing and automatic knowledge acquisition from data bases.
Coupling and power handling of the new Tore Supra LHCD launcher
Bibet, Ph. E-mail: bibet@drfc.cad.cea.fr; Ekedahl, A.; Froissard, Ph.; Kazarian, F.; Bertrand, E.; Dutheil, S.; Tanaskovic, L
2001-10-01
A new LHCD launcher, designed to inject 4 MW during 1000 s, has been installed on Tore Supra and successfully tested. A power of 3 MW with 7% power reflection coefficient has been reached. The coupling has been studied for various plasma parameters and positions, in order to study the robustness of the mode converter used in the antenna to divide the power into three in the poloidal direction. Due to the reduced electric field and the very efficiently water-cooled guard limiter, the temperature increase induced by the acceleration of electrons in the near field has been drastically reduced.
R&D activities on RF contacts for the ITER ion cyclotron resonance heating launcher
Hillairet, Julien, E-mail: julien.hillairet@cea.fr [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Argouarch, Arnaud [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Bamber, Rob [CCFE, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Beaumont, Bertrand [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Bernard, Jean-Michel; Delaplanche, Jean-Marc [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Durodié, Frédéric [Laboratory for Plasmas Physics, 1000 Brussels (Belgium); Lamalle, Philippe [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Lombard, Gilles [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Nicholls, Keith; Shannon, Mark [CCFE, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Vulliez, Karl [Maestral Laboratory, Technetics Group, Pierrelatte (France); Cantone, Vincent; Hatchressian, Jean-Claude; Larroque, Sébastien; Lebourg, Philippe; Martinez, André; Mollard, Patrick; Mouyon, David; Pagano, Marco [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); and others
2015-10-15
Highlights: • CEA have developed a dedicated test-bed for testing RF contact in ITER relevant conditions (vacuum, temperature, RF current). • A prototype of RF contacts have been designed and manufactured, with copper lamellas brazed on a titanium holder. • This RF contact prototype failed at RF current larger than 1.8 kA. • Extensive R&D is foreseen with new RF contact designs. - Abstract: Embedded RF contacts are integrated within the ITER ICRH launcher to allow assembling, sliding and to lower the thermo-mechanical stress. They have to withstand a peak RF current up to 2.5 kA at 55 MHz in steady-state conditions, in the vacuum environment of the machine. The contacts have to sustain a temperature up to 250 °C during several days in baking operations and have to be reliable during the whole life of the launcher without degradation. The RF contacts are critical components for the launcher performance and intensive R&D is therefore required, since no RF contacts have so far been qualified at these specifications. In order to test and validate the anticipated RF contacts in operational conditions, CEA has prepared a test platform consisting of a steady-state vacuum pumped RF resonator. In collaboration with ITER Organization and the CYCLE consortium (CYclotron CLuster for Europe), an R&D program has been conducted to develop RF contacts that meet the ITER ICRH launcher specifications. A design proposed by CYCLE consortium, using brazed lamellas supported by a spring to improve thermal exchange efficiency while guaranteeing high contact force, was tested successfully in the T-resonator up to 1.7 kA during 1200 s, but failed for larger current values due to a degradation of the contacts. Details concerning the manufacturing of the brazed contacts on its titanium holder, the RF tests results performed on the resonator and the non-destructive tests analysis of the contacts are given in this paper.
Utilizing NX Advanced Simulation for NASA's New Mobile Launcher for Ares-l
Brown, Christopher
2010-01-01
This slide presentation reviews the use of NX to simulate the new Mobile Launcher (ML) for the Ares-I. It includes: a comparison of the sizes of the Saturn 5, the Space Shuttle, the Ares I, and the Ares V, with the height, and payload capability; the loads control plan; drawings of the base framing, the underside of the ML, beam arrangement, and the finished base and the origin of the 3D CAD data. It also reviews the modeling approach, meshing. the assembly Finite Element Modeling, the model summary. and beam improvements.
Structural requirements and basic design concepts for a two-stage winged launcher system (Saenger)
Kuczera, H.; Keller, K.; Kunz, R.
1988-10-01
An evaluation is made of materials and structures technologies deemed capable of increasing the mass fraction-to-orbit of the Saenger two-stage launcher system while adequately addressing thermal-control and cryogenic fuel storage insulation problems. Except in its leading edges, nose cone, and airbreathing propulsion system air intakes, Ti alloy-based materials will be the basis of the airframe primary structure. Lightweight metallic thermal-protection measures will be employed. Attention is given to the design of the large lower stage element of Saenger.
张志华; 史黎明; 蔡华; 李耀华
2015-01-01
The braking performance of long primary double-sided linear induction motor (DSLIM) is influenced by longitudinal dynamic end effect, which results from the difference of secondary covered and rest air-gap filed. Analysis model of long primary DSLIM was established, formulas for flux density of air-gap and braking force were deduced by considering transverse and longitudinal dynamic end effects. The relations that braking force with slip, G-factor, secondary speed and conductivity, etc were analyzed. Comparative analysis shows that the longitudinal dynamic end effect is waken when slip approximates zero under regenerative braking and is aggravated when force reaches maximum under DC dynamic braking. Increasing secondary covered poles and braking in low slip of motor can restrain longitudinal dynamic end effect. Lastly, 3D finite element model (FEM) of prototype was built to obtain the flux density distribution and DC dynamic braking force. Simulation and experiment results verify the feasibility and effectiveness of the calculation method.%长初级双边直线感应电机(double-sided linear induction motor,DSLIM)制动时短次级作用区域与未作用区域的气隙磁场不同,造成的纵向动态边端效应对电机制动性能产生一定影响.该文建立长初级DSLIM解析模型,在考虑电机横向边端效应与纵向动态边端效应的基础上,推导长初级DSLIM回馈制动与直流能耗制动时气隙磁密和制动力解析公式,分析长初级DSLIM随滑差率、品质因数、次级速度、次级电阻等参数变化下的制动特性,定量分析纵向动态边端效应对回馈制动与直流能耗制动的不同影响.研究显示电机回馈制动时的纵向动态边端效应在滑差率接近零时变小,直流能耗制动时的纵向动态边端效应在最大制动力时最强,通过增加次级作用区域极数和电机低滑差率制动能有效抑制纵向动态边端效应.建立了一台实验样机三维有限元模型,
关晓存; 雷彬; 李治源; 赵然
2011-01-01
According to actual structure of a high-speed multi-stage cylinder linear induction motor （HSMCLIM） based on electromagnetic field theory, the mathematical model of the motor is deduced, which considers inter-stage coupling effect. In case of with and without considering inter-stage, stator current, armature accelerating force and speed, motor energy efficiency are discussed Results indicate that inter-stage coupling effect is favorable for motor efficiency. Finally, model machines of motors are fabricated and experimented, and armature speed in each stage is measured. Experimental results compare with simulation results, they coincide well.%基于高速多级圆筒型直线感应电机特殊的结构，利用电磁场理论，推导了考虑级间耦合的数学模型，并利用该模型分析了考虑级间耦合和不考虑级间耦合情况下，各级定子绕组电流、动子加速力和速度、电机能效率之间的区别。对比结果表明，级间耦合效应有利于电机的运行性能。最后，对这两种情况下样机实验，测得各级中动子的速度，并与仿真结果对比，两者吻合较好。
赵佳; 张威; 方进; 杨中平; 郑琼林; 刘友梅
2011-01-01
A new type high temperature superconductor linear induction motor (HTS LIM) is designed. The primary windings are made of Bi-2223/Ag. And the motor is the single-layer concentrated structure. The critical current of the motor is determined mainly by the primary slot leakage flux.The electromagnetic force is decided mainly by the air magnetic flux and the eddy current of the secondary plate. The structural parameters of the motor have a great impact on the distribution of the magnetic field. Under constant currents the steady and transient properties of the motor were analyzed with different slot width, slot height and winding tums. The properties of the motor, such as the maximum slot leakage flux,the motor thrust and the motor vertical force, were analyzed with different structural parameters.%设计了一种新型高温超导直线感应电机,初级线圈为Bi-2223/Ag高温超导线圈,采用单层整距集中绕组结构排列.高温超导直线感应电机临界电流的大小主要由电机初级槽漏磁通密度决定,电磁力的人小主要由空气主磁通和次级感应板涡流决定.电机结构参数对电机磁场的分布影响很大.使用有限元法比较分析了恒流条件下电机槽宽、槽高和绕组匝数对电机稳态和瞬态电磁性能的影响,研究了电机结构参数对电机最大槽漏磁通密度、电机推力和电机垂向力的影响.
王远; 张开志; 江孝国; 杨国君; 李劲
2009-01-01
强流脉冲电子束作为一种高亮度的光源,具有广阔的应用前景,而双轴束流测量的控制对于研究产生电子束的加速器技术具有重要意义;利用多线程技术在CVI环境下的实现方法,研究了双路束流参数特点、双路束流测量的时序同步控制方法,在此基础上采用线程池多线程技术实现基于TCP/IP的加速器束流测量的数据采集软件,结果表明采用多线程技术可以很好地实现多任务的同时工作,有助于提高束测量的响应速度和测量的执行效率.%The intense current pulsed electron beam is a new kind of light source with very high brightness and is very useful. The control technology of double axial orientation electron beam measurement is very important for the study of linear induction accelerator (LIA)which produce the electron beam. In order to meet the demand of measuring the double electron beam by Muhithreading Technology, a new method for the beam measurement and synchronous control has been developed, the software of beam measurement of accelerator can be implemented with multithreading technology by TCP/IP; The method can ensure synchronous work by multithreading technology and the method can improve response speed and measurement efficiency.
Sprogøe, Jonas; Rohde, Nicolas
2009-01-01
We claim that induction potentially triggers both individual and organizational learning and by drawing on practice-based theory we discuss how the interplay between individual and organization, what we call a generative dance, ignites both kinds of learning....
Structure and Design of Storage and Transport Launcher%贮运发射箱的结构与设计
陈愚; 孙凤云
2012-01-01
Advantages and uses of storage and transport launcher were introduced. The basic constitution of general storage and transport launcher was analyzed. The advantages and disadvantage of different type＇s box body, box kid, and direction tinder were discussed. The design basis and principles of storage and transport launcher were put forward.%简述了贮运发射箱的优点和用途,介绍了通用贮运发射箱的基本构成,着重对贮运发射箱不同类型的箱体、箱盖、定向器的优缺点进行了阐述,指出了贮运发射箱的设计原则和设计依据。
Beam propagation and stray radiation in the ITER EC H&CD Upper Launcher
Platania Paola
2015-01-01
Hydrodynamic instabilities with the deposition of Electron Cyclotron power. According to the present design, each launcher comprises two rows of four input waveguides, whose output beam is focused and driven towards the plasma by four sets of mirrors. In order to study the beam-launcher interaction throughout quasi-optical propagation, with particular attention to straylight behaviour, and to verify analytical calculations, a 3D model of the UL optical system has been implemented with the electromagnetic code GRASP® and the Physical Optics method. Detailed description of the components are introduced: pure hybrid mode HE11 from cylindrical waveguide as input beams, real shapes of the mirror contours, semi-analytical description of the ellipsoidal surfaces of focussing mirrors. A conceptual calculation scheme has been developed in order to take into account not only the direct contribution of the single source on its next scatterer but also the first order indirect effects: crosstalk from different lines of the same row and crosstalk from different rows have been evaluated after reflection on the first and third set of mirrors. The evaluations presented have been performed on the preliminary UL design, the last major milestone before finalization; however, the numerical model is suitable to be applied to future evolutions of the setup and/or other configurations.
Rice, E. E.; Miller, L. A.; Marshall, R. A.; Kerslake, W. R.
1982-01-01
The feasibility of earth-to-space electromagnetic (railgun) launchers (ESRL) is considered, in order to determine their technical practicality and economic viability. The potential applications of the launcher include nuclear waste disposal into space, deep space probe launches, and atmospheric research. Examples of performance requirements of the ESRL system are a maximum acceleration of 10,000 g's for nuclear waste disposal in space (NWDS) missions and 2,500 g's for earth orbital missions, a 20 km/sec launch velocity for NWDS missions, and a launch azimuth of 90 degrees E. A brief configuration description is given, and test results indicate that for the 2020-2050 time period, as much as 3.0 MT per day of bulk material could be launched, and about 0.5 MT per day of high-level nuclear waste could be launched. For earth orbital missions, a significant projectile mass was approximately 6.5 MT, and an integral distributed energy store launch system demonstrated a good potential performance. ESRL prove to be economically and environmentally feasible, but an operational ESRL of the proposed size is not considered achievable before the year 2020.
Rice, E. E.; Miller, L. A.; Marshall, R. A.; Kerslake, W. R.
1982-01-01
The feasibility of earth-to-space electromagnetic (railgun) launchers (ESRL) is considered, in order to determine their technical practicality and economic viability. The potential applications of the launcher include nuclear waste disposal into space, deep space probe launches, and atmospheric research. Examples of performance requirements of the ESRL system are a maximum acceleration of 10,000 g's for nuclear waste disposal in space (NWDS) missions and 2,500 g's for earth orbital missions, a 20 km/sec launch velocity for NWDS missions, and a launch azimuth of 90 degrees E. A brief configuration description is given, and test results indicate that for the 2020-2050 time period, as much as 3.0 MT per day of bulk material could be launched, and about 0.5 MT per day of high-level nuclear waste could be launched. For earth orbital missions, a significant projectile mass was approximately 6.5 MT, and an integral distributed energy store launch system demonstrated a good potential performance. ESRL prove to be economically and environmentally feasible, but an operational ESRL of the proposed size is not considered achievable before the year 2020.
Using distributed magnetometry in navigation of heavy launchers and space vehicles
Praly, N.; Bristeau, P.-J.; Laurent-Varin, J.; Petit, N.
2013-12-01
Recently, a new technique (magneto-inertial navigation, MINAV) has emerged to address the general problem of reconstructing the inertial velocity of a rigid body moving in a magnetically disturbed region. The contribution of this paper is to apply the developed method, in a prospective spirit, to a case of space navigation in view of estimating the performance improvement that could be obtained using state-of-theart magnetometer technology onboard heavy launchers and other space vehicles. The main underlying idea of the approach is to estimate the inertial velocity by readings of the magnetic field at spatially distributed (known) locations on the rigid body. Mathematically, through a chainrule differentiation involving variables commonly appearing in classic inertial navigation, an estimate of this velocity can be obtained. This paper presents the potential of this method in the field of navigation of heavy launchers passing through particular regions of the Earth magnetosphere as considered, e. g., for upcoming Galileo missions. Numerical results based on the specifications of candidate embedded magnetic sensors stress the relevance of the approach. The presented methodology is patent pending and has been partially funded by CNES.
Analysis of the ITER ECH Upper Port Launcher remote maintenance using virtual reality
Elzendoorn, Ben [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster and ITER-NL, PO Box 1207, 3430 BE Nieuwegein (Netherlands)], E-mail: ben@rijnh.nl; de Baar, Marco [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster and ITER-NL, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Chavan, Rene; Goodman, Timothy [CRPP, EURATOM - Confederation Suisse, EPFL, CH-1015 Lausanne (Switzerland); Heemskerk, Cock [Heemskerk Innovative Technology, Merelhof 2, 2172 HZ Sassenheim (Netherlands)], E-mail: c.heemskerk@heemskerk-innovative.nl; Heidinger, Roland; Kleefeldt, Klaus [Forschungszentrum Karlsruhe, Association FZK-Euratom, D-76021 Karlsruhe (Germany); Koning, Jarich [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster and ITER-NL, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Sanders, Stephen [OTL, Oxford Technologies Ltd., Abingdon (United Kingdom); Spaeh, Peter; Strauss, Dirk [Forschungszentrum Karlsruhe, Association FZK-Euratom, D-76021 Karlsruhe (Germany); Verhoeven, Toon [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster and ITER-NL, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Vreede, Fred de [TNO Science and Industry, partner in ITER-NL, PO Box 155, 2600 AD Delft (Netherlands)
2009-06-15
All ITER sub-systems of remote handling (RH) classes 1 and 2 have to be remotely maintainable. The maintenance strategy for these components has to ensure system availability after failure or scheduled maintenance. This paper shows how virtual reality (VR) simulation can be used as a tool to analyze the maintenance process, to predict the mean time to repair and to ensure the RH compatibility of one ITER sub-system, the Upper Port Launcher (UPL) . Special emphasis is put on the development of RH procedures and the identification of tooling requirements. The possibility to simulate RH logistics and repair actions in an early stage of the design process allows for the identification of those maintenance actions that require dedicated tests in the Launcher Handling Test Facility at Karlsruhe. The VR analysis, together with dedicated mock-up tests will demonstrate the RH compatibility of the UPL plug, provide input to the design of the Port Plug maintenance area in the ITER Hot Cell, and support the development of RH maintenance tooling.
Recent advance on design and manufacturing of composite anisogrid structures for space launchers
Totaro, G.; De Nicola, F.
2012-12-01
Anisogrid composite shells have been developed and applied since the eighties by the Russian technology aiming at critical weight structures for space launchers, as interstages and cone adapters. The manufacturing process commonly applied is based on the wet filament winding. The paper concerns with some developments of design and manufacturing recently performed at the Italian Aerospace Research Center on a cylindrical structural model representative of this kind of structures. The framework of preliminary design is improved by introducing the concept of suboptimal configuration in order to match the stiffness requirement of the shell and minimise the mass, in conjunction with the typical strength constraints. The undertaken manufacturing process is based on dry robotic winding for the lattice structure and for the outer skin, with the aid of usual rubber tooling and new devices for the automated deposition strategy. Resin infusion under vacuum bag and co-cure of the system of ribs and skin is finally applied out-of-autoclave, with the aid of a heated mandrel. With such approach an interstage structural model (scale factor 1:1.5) has been designed, manufactured and tested. Design requirements and loads refer to a typical space launcher whose baseline configuration is made in aluminium. The global mechanical test of the manufactured structure has confirmed the expected high structural performance. The possibility to reach substantial weight savings in comparison with the aluminium benchmark has been fully demonstrated.
Igra, Ozer
2016-01-01
In the present volume numerous descriptions of Ram accelerators are presented. These descriptions provide good overview on the progress made and the present state of the Ram accelerator technology worldwide. In addition, articles describing light gas gun, ballistic range including a chapter dealing with shock waves in solids are given. Along with the technical description of considered facilities, samples of obtained results are also included. Each chapter is written by an expert in the described topic providing a comprehensive description of the discussed phenomena. .
Induction of formaldehyde contact sensitivity
Andersen, Klaus Ejner; Boman, A; Vølund, A
1985-01-01
intradermal induction with 0.65% formaldehyde; in Stockholm it was 84% after induction with 0.34%. The data from the two laboratories could be described by parallel displaced dose response curves suggesting that the guinea pig strain used in Stockholm was significantly more susceptible to formaldehyde than......, and formaldehyde 1% and 0.1% was used for challenge. The incidence of contact sensitivity depended on the intradermal, but not on the topical induction dose. Statistical analyses showed a non-monotonous (non-linear) dose response relationship. The estimated maximal sensitization rate in Copenhagen was 80% after...
Henningsen, Poul
. The method has proven to give successful results in brazing tube-plate joints of copper-brass, copper-stainless steel, stainless steel-brass, and stainless steel-stainless steel. A new design of an adjustable flux concentrator for induction heating tube-to-plate joints is proposed and tested on a variety......Induction brazing is a fast and appropriate method for industrial joining of complex geometries and metal combinations. In all types of brazing processes it is important to heat the joint interface of the two materials to the same, high temperature. If one of the specimens is warmer than the other...... materials has large influence on the heating time and temperature distribution in induction heating. In order to ensure high and uniform temperature distribution near the interface of a joint between dissimilar materials the precise coil geometry and position is of great importance. The present report...
LI Ye-nong; PENG Shu-hua; ZHANG Li-ping; SHI Zhu-kang
2011-01-01
The transmission mechanism of a jack is required to support the combat vehicle reliably within a very short time. So reliability research is very important because the mechanism completes motions required under the conditions within limited time. If the transmission mechanism of the jack supports the rocket launcher steadily, it needs to go through several stages as follows ： unlocking, starting, operating, braking, stopping, fixing position and locking. The transmission mechanism of the jack is a complicated and single degree of freedom mechanical system; it can be considered an imaginary mechanical model that has an equivalent moment of inertia and equivalent torque. According to the characteristics of each supporting stages, dynamics equations of the mechanism are established. At the stages of starting and operating, a driving moment and resistance moment are dealt with for a Normal distribution. The design principles for movement reliability of completing action are established and the design principles for time reliability of completing action within a limited time are established. Finally, movement reliability of the transmission mechanism of the jack is 0. 9 852, according to our calculation. Reliability of time to complete action is 0. 9 943.
Speed-Sensorless Vector Control of Primary Cascaded Linear Induction Motor%初级级联直线感应电机的无速度传感器矢量控制
马家庆; 周大进; 赵立峰; 张勇; 赵勇
2015-01-01
For investigating the performance of constant and adaptive speed regulation of cascaded linear induction motor (LIM)in maglev system,a new speed-sensorless vector controller was designed based on the Maxwell equations by analyzing the relationship between the thrust of the LIM and the current vector of the primary winding. The reasonability and the effectiveness of this controller were verified by numerical simulation using Matlab/Simulink. The results show that when facing small perturbation of the speed,the controller can automatically adjust the DC bus voltage of the rectifier through the inner current loop and the outer voltage loop to stabilize the speed within 10 ms. When receiving the reference speed value,the frequency of the AC side of the inverter is regulated to obtain a suitable value of the synchronous speed;the regulating time is less than 50 ms and within 3 cycles of power frequency,meeting the requirements of control performance in maglev system.%为了研究磁浮系统中的恒速驱动及适时速度调节性能，根据Maxwell方程及电机的矢量控制原理，以磁浮系统中的直线感应电动机为研究对象，在其推力与初级绕组中电流矢量关系的基础上，设计了无速度传感器矢量控制器，并利用Matlab／Simulink软件验证控制器的正确性。研究结果表明：当速度在小范围内受扰动时，控制器运用电流内环、电压外环控制方式自动调节整流器的直流母线电压，调节时间小于10 ms；当控制器接收到指令速度时，改变逆变器的频率，该频率改变电机同步速，达到调速的目的，调节时间小于50 ms，表明在工频小于3个周期时，满足磁浮系统的控制要求。
Field Oriented Control of Linear Induction Machine Based on Fuzzy Control%模糊控制在直线感应电机磁场定向控制中的应用
张云红; 曾成碧; 徐伟; 肖先勇
2012-01-01
Because the single-sided linear induction machine (SLIM) is equivalent to a rotary machine cut open and rolled flat, they are with similar performance. However, by the reason of longitudinal end effect, the parameters of SLIM, particularly excitation inductor, are changeable when the machine runs. For such a nonlinear and time-varying system, conventional PI control can not meet the requirement of high performance. Fuzzy control doesn' t depend on the mathematical model of the controlled object, and is able to imitate human thinking to control the object intelligently. Combining the advantages of PI control and fuzzy control, a fuzzy self-adapting PI controller was designed, which was applied in the rotor field oriented control of SLIM in order to study the properties of SLIM. Simulations showed that the proposed control method is able to eliminate the steady-state error effectively and has better performance of transient state.%单边直线感应电机相当于旋转电机沿半径剖开并平展,性能与旋转电机类似,但由于受纵向边端效应影响,电机参数,尤其是励磁电感,随电机运行速度和滑差而改变.对于该非线性时变系统,传统PI控制难以满足高性能的要求.模糊控制不依赖控制对象的具体数学模型,能模仿人的思维对电机驱动系统进行智能控制.结合PI控制和模糊控制的优点,设计了模糊自适应PI控制器,并将其应用于单边直线感应电机转子磁场定向控制中,以研究电机的特性.大量仿真结果表明,该方法能有效消除控制参数的稳态误差,同时具有较好的暂态性能.
Gildeberto S. Cardoso
2011-01-01
Full Text Available This paper presents a study of linear control systems based on exact feedback linearization and approximate feedback linearization. As exact feedback linearization is applied, a linear controller can perform the control objectives. The approximate feedback linearization is required when a nonlinear system presents a noninvolutive property. It uses a Taylor series expansion in order to compute a nonlinear transformation of coordinates to satisfy the involutivity conditions.
A socio-economic impact assessment of the European launcher sector
Monte, Luca del; Scatteia, Luigi
2017-08-01
In a context where the economic strains are challenging European policies as well as the very fabric of governmental contributions to public life, innovation and efficacy of public policy in research are called upon to support growth in Europe and to sustain employment and entrepreneurial capacities. Governments need evidence that the investments in space, while providing strategic tools to implement sovereign policies, create jobs and build the competitive European economy of the future. This is particularly true when the decisions at stake have a potential bearing on the future of the European space sector for at least the next 30 years, as it has been the case for the ESA Council at ministerial level meeting in December 2014. On that occasion, Ministers took the decision to start the development of a new Ariane 6 launcher and Vega evolutions having a critical bearing on the Member States' strategic industrial capabilities and on the sustainability of the European guaranteed access to space. Given the importance of the subject, and following similar studies undertaken in the past for e.g. the Ariane 1-4 programme, the Agency has requested an independent consulting team to perform a dedicated study to assess ex-post the direct, indirect and induced socio-economic impacts of the Ariane 5 programme (mid-term evaluation) and of the Vega programme (early evaluation) globally, at European level, and within the economies and industries of each ESA Member State. This paper presents the assessment of the socio-economic impacts allowing the evaluation of the return on public investments in launchers through ESA in a wider perspective, going beyond the purely economic terms. The scope of the assessment covered in total approximately 25 ESA programmatic and activity lines and 30,000 commitments from 1986 to end 2012. In the framework of the study, the economic impact of the European launcher programmes is measured through a GDP impact defined as the straight economic
一种新型复合材料发射管的设计%Design of a new composite launcher tube
蔡德咏; 马大为; 赵英英; 胡建国
2011-01-01
Selected ceramic matrix composites (CMCs)and hybrid fiber reinforced polymer(HFRP) composites as material,designed a lightweight launcher tube which can be used repeatedly. Established the finite element model of new launcher tube, the simulation calculation of rocket launching was carried out. Compare with metal launcher tube and glass fiber reinforced plastics launcher tube, the results indicate that the stiffness and strength of new type launcher tube can meet the requirements. The new type launcher tube had a good performance with the weight was only 24.36％ of the metal launcher tube, and it can be used repeatedly.%选用陶瓷基复合材料和混杂增强树脂基复合材料设计了一种轻型并可重复使用的发射管.建立新型发射管有限元模型,进行了火箭发射的数值仿真,并与金属发射管、玻璃钢发射管进行了对比研究.结果表明新型复合材料火箭发射管的刚度、强度都满足要求,性能良好,并可重复使用,而质量只有金属管的24.36%.
Capabilities of the ITER Electron Cyclotron Equatorial Launcher for Heating and Current Drive
Ramponi G.
2012-09-01
Full Text Available The ITER Electron Cyclotron Equatorial Launcher is designed to be one of the heating systems to assist and sustain the development of various ITER plasma scenarios starting with the very first plasma operation. Here the capabilities for Heating and Current Drive of this system are reviewed. In particular, the optimum launching conditions are investigated for two scenarios at burn, comparing toroidal and poloidal steering options. Then, the EC capabilities are investigated for different plasma parameters corresponding to various phases of the ITER plasma discharge, from current ramp-up up to burn, and for a wide range of magnetic field, focusing in particular on the EC potential for heating and for L to H-mode assist. It is found that the EC system can contribute to a wide range of heating scenarios during the ramp-up of the magnetic field, significantly increasing the applicable range as a function of magnetic field.
Specifications and implementation of the RT MHD control system for the EC launcher of FTU
Nowak S.
2012-09-01
Full Text Available To perform real time plasma control experiments using EC heating waves by using the new fast launcher installed on FTU a dedicated data acquisition and elaboration system has been designed recently. A prototypical version of the acquisition/control system has been recently developed and will be tested on FTU machine in its next experimental campaign. The open-source framework MARTe (Multi-threaded Application Real-Time executor on Linux/RTAI real-time operating system has been chosen as software platform to realize the control system. Standard open-architecture industrial PCs, based either on VME bus and CompactPCI bus equipped with standard input/output cards are the chosen hardware platform.
On the criteria guiding the design of the upper electron-cyclotron launcher for ITER
Poli E.
2015-01-01
Full Text Available Electron cyclotron waves injected from an antenna located in the upper part of the vessel will be employed in ITER to controlMHD instabilities, particularly neoclassical tearingmodes (NTMs. The derivation of the NTM stabilization criteria used up to now to guide the optimization of the launcher is reviewed in this paper and their range of validity elucidated. Possible effects leading to a deterioration of the predicted performance through a broadening of the EC deposition profile are discussed. The most detrimental effect will likely be the scattering of the EC beams from density fluctuations, resulting in a beam broadening in the 100% range. The combined impact of these effects with that of beam misalignment (with respect to the targeted surface is discussed for a time slice of the standard Q = 10 H-mode scenario.
Deformation Calculating of Electromagnetic Launcher's Rail Subjected to Sinusoidal Magnetic Pressure
Liu Wen
2011-01-01
Full Text Available The electromagnetic launcher's rail can be modeled as a beam on elastic foundation with simply supported beam by moving load. In this paper, Euler beam theory is applied to build the mechanical model, and the analytical solution of the equation subjected to sinusoidal magnetic pressure is derived in detail, which has successfully avoided the errors which are caused by using the uniform pressure to approximately replace the variable force. Numerical analysis of the influences brought from the elastic coefficient, the damping coefficient, the mass of rail, and the load's velocity on the deformation of beam by the MATLAB software show that the elastic coefficient and the load's velocity have quite obvious effect on the deformation of the beam while the damping coefficient and the mass of rail have not obvious effect on the deformation of the beam.
Very High Specific Energy, Medium Power Li/CFx Primary Battery for Launchers and Space Probes
Brochard, Paul; Godillot, Gerome; Peres, Jean Paul; Corbin, Julien; Espinosa, Amaya
2014-08-01
Benchmark with existing technologies shows the advantages of the lithium-fluorinated carbon (Li/CFx) technology for use aboard future launchers in terms of a low Total Cost of Ownership (TCO), especially for high energy demanding missions such as re-ignitable upper stages for long GTO+ missions and probes for deep space exploration.This paper presents the new results obtained on this chemistry in terms of electrical and climatic performances, abuse tests and life tests. Studies - co-financed between CNES and Saft - looked at a pure CFx version with a specific energy up to 500 Wh/kg along with a medium power of 80 to 100 W/kg.
ITER ECH and CD Upper Launcher: Design options and Remote Handling issues of the waveguide assembly
Grossetti, G., E-mail: giovanni.grossetti@kit.edu [Karlsruhe Institute of Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Aiello, G. [Karlsruhe Institute of Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Chavan, R. [CRPP, EURATOM – Confédération Suisse, EPFL, CH-1015 Lausanne (Switzerland); Geßner, R. [Karlsruhe Institute of Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Goodman, T. [CRPP, EURATOM – Confédération Suisse, EPFL, CH-1015 Lausanne (Switzerland); Heemskerk, C. [Heemskerk Innovative Technology, Merelhof 2, 2172 HZ Sassenheim (Netherlands); Meier, A. [Karlsruhe Institute of Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Ronden, D. [FOM Institute DIFFER, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Scherer, T.; Späh, P.; Schreck, S.; Strauß, D.; Vaccaro, A. [Karlsruhe Institute of Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Van Oosterhout, J. [FOM Institute DIFFER, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands)
2014-10-15
Highlights: • Paper deals with ITER Electron Cyclotron Heating and Current Drive Upper Launcher. • Design options and Remote Handling issues related to the waveguide assembly have been investigated. • Description of preliminary assessments on the RH compatibility of the sub-assembly is shown. • Assessment on possible replacement procedure and the required tools are presented. - Abstract: The ITER Electron Cyclotron Heating and Current Drive Upper Launcher, developed by the ECHUL-CA Consortium of Euratom Associations (CRPP, CNR, ITER-NL, IPF, IPP, KIT and Politecnico di Milano), is presently in its final design phase. The study presented here deals with design options and Remote Handling issues related to the waveguide assembly, an ensemble of mm-wave transmission line components mounted on a vacuum flange. This flange is part of the primary vacuum boundary of the ITER vessel. This paper describes the preliminary assessment of the RH compatibility of the sub-assembly, and a conceptual description of the maintenance actions to be performed on it. A comparison between two possible configurations for the tapers is reported: a waveguide integrated design, in which tapers are integral part of the in-plug waveguide, and an auxiliary shield integrated design, in which the tapers are integrated into the Auxiliary Shield. An important aspect in the design is to ensure the Remote Handling compatibility. Due to lack of space and limited dexterity of the slave manipulator, the general approach in defining the maintenance strategy is to avoid breaking the interfaces of the different components of the assembly, and to extract it from the Upper Port Plug as a single entity. An assessment on possible replacement procedure and the required tools are presented here.
Shilov, Georgi E
1977-01-01
Covers determinants, linear spaces, systems of linear equations, linear functions of a vector argument, coordinate transformations, the canonical form of the matrix of a linear operator, bilinear and quadratic forms, Euclidean spaces, unitary spaces, quadratic forms in Euclidean and unitary spaces, finite-dimensional space. Problems with hints and answers.
Agarwalla Arun
2001-01-01
Full Text Available Linear psoriasis, inflammatory linear varrucous epidermal naevus (ILVEN. Lichen straitus, linear lichen planus and invasion of epidermal naevi by psoriasis have clinical and histopathological overlap. We report two young male patients of true linear psoriasis without classical lesions elsewhere which were proved histopathologically. Seasonal variation and good response to topical antipsoriatic treatment supported the diagnosis.
Sander, K F
1964-01-01
Linear Network Theory covers the significant algebraic aspect of network theory, with minimal reference to practical circuits. The book begins the presentation of network analysis with the exposition of networks containing resistances only, and follows it up with a discussion of networks involving inductance and capacity by way of the differential equations. Classification and description of certain networks, equivalent networks, filter circuits, and network functions are also covered. Electrical engineers, technicians, electronics engineers, electricians, and students learning the intricacies
Rohde, Nicolas; Sprogøe, Jonas
2007-01-01
that induction potentially triggers both individual and organizational learning and by drawing on practice-based theory we discuss how the interplay between individual and the organization, what we call agenerative dance, ignites both kinds of learning. We focus on and describe the interplay , ignites both kinds...... of learning. We focus on and describe the interplay that takes place in particular induction events and analyze the "dance" through the lens of learning. The paper concludes with a brief discussion about the implications for practitioners and the challenges and future research prospects we have encountered....... We draw on an empirical enquiry in two organizational settings, a Danish management consulting company and a German retail bank....
Inductively Coupled Augmented Railgun
Bahder, Thomas B
2011-01-01
We derive the non-linear dynamical equations for an augmented electromagnetic railgun, whose augmentation circuit is inductively coupled to the gun circuit. We solve these differential equations numerically using example parameter values. We find a complicated interaction between the augmentation circuit, gun circuit, and mechanical degrees of freedom, leading to a complicated optimization problem. For certain values of parameters, we find that an augmented electromagnetic railgun has an armature kinetic energy that is 42% larger than the same railgun with no augmentation circuit. Optimizing the parameters may lead to further increase in performance.
2003-01-01
A translation system, applicable in trains, elevators, aircraft launchers, rail guns, conveyors, door openers, machine tools and servo drives, includes a first linear switch reluctance machine (“LSRM”) having a stator and a translator each configured, positioned and proportioned for electromagentic engagement with the other. The system further includes an assembly for selectable application of at least one phase of a multiphasic DC excitation to the LSRM to produce a longitudinal or propulsiv...
Henningsen, Poul
, or if the hottest area is located outside the joint interface, a number of defects may appear: the braze metal may flow away from the joint, the flux may burn off, poor binding of the braze metal may appear or the braze metal may be overheated. Joint geometry as well as electro-magnetic properties of the work piece......Induction brazing is a fast and appropriate method for industrial joining of complex geometries and metal combinations. In all types of brazing processes it is important to heat the joint interface of the two materials to the same, high temperature. If one of the specimens is warmer than the other...
Experimental characterization and modeling of non-linear coupling of the LHCD power on Tore Supra
Preynas, M.; Goniche, M.; Hillairet, J.; Litaudon, X.; Ekedahl, A.
2014-02-01
To achieve steady state operation on future tokamaks, in particular on ITER, the unique capability of a LHCD system to efficiently drive off-axis non-inductive current is needed. In this context, it is of prime importance to study and master the coupling of LH wave to the core plasma at high power density (tens of MW/m2). In some specific conditions, deleterious effects on the LHCD coupling are sometimes observed on Tore Supra. At high power the waves may modify the edge parameters that change the wave coupling properties in a non-linear manner. In this way, dedicated LHCD experiments have been performed using the LHCD system of Tore Supra, composed of two different conceptual designs of launcher: the Fully Active Multijunction (FAM) and the new Passive Active Multijunction (PAM) antennas. A nonlinear interaction between the electron density and the electric field has been characterized in a thin plasma layer in front of the two LHCD antennas. The resulting dependence of the power reflection coefficient with the LHCD power, leading occasionally to trips in the output power, is not predicted by the standard linear theory of the LH wave coupling. Therefore, it is important to investigate and understand the possible origin of such non-linear effects in order to avoid their possible deleterious consequences. The PICCOLO-2D code, which self-consistently treats the wave propagation in the antenna vicinity and its interaction with the local edge plasma density, is used to simulate Tore Supra discharges. The simulation reproduces very well the occurrence of a non-linear behavior in the coupling observed in the LHCD experiments. The important differences and trends between the FAM and the PAM antennas, especially a larger increase in RC for the FAM, are also reproduced by the PICCOLO-2D simulation. The working hypothesis of the contribution of the ponderomotive effect in the non-linear observations of LHCD coupling is therefore validated through this comprehensive modeling
Grossetti, Giovanni, E-mail: giovanni.grossetti@kit.edu [Karlsruhe Institute of Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Aiello, Gaetano [Karlsruhe Institute of Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Heemskerk, Cock [Heemskerk Innovative Technology, Merelhof 2, 2172 HZ Sassenheim (Netherlands); Elzendoorn, Ben [FOM Institute DIFFER, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Geßner, Robby [Karlsruhe Institute of Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Koning, Jarich [Heemskerk Innovative Technology, Merelhof 2, 2172 HZ Sassenheim (Netherlands); Meier, Andreas [Karlsruhe Institute of Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Ronden, Dennis [FOM Institute DIFFER, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Späh, Peter; Scherer, Theo; Schreck, Sabine; Strauß, Dirk; Vaccaro, Alessandro [Karlsruhe Institute of Technology, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany)
2013-10-15
This paper deals with Remote Handling activities foreseen on the Blanket Shield Module, the plasma facing component of the ITER Electron Cyclotron Heating and Current Drive Upper Launcher. The maintenance configuration considered here is the Vertical Remote Handling, meaning gravity acting along the launcher radial axis. The plant, where the maintenance under consideration is occurring, is the Hot Cell Facility Work Cell. The study here reported has been carried out within the presently ongoing EFDA Goal Oriented Training program on Remote Handling (GOT-RH), which aims to support ITER activities. This document and its contents have to be considered as part of a more vast RAMI analysis to be developed within the GOT-RH, which aims to maximize the Electron Cyclotron Heating and Current Drive system availability. The Baseline CAD model of the Electron Cyclotron Heating and Current Drive Upper Launcher is currently in its preliminary design phase and does not provide enough details for developing a fully detailed maintenance strategy. Therefore, through a System Engineering approach, a set of assumptions was conceived on the launcher structure, as a basis for development of a Remote Handling strategy. Moreover, to compare different design solutions related to the possibility of integrating a quasi-optical component into the Blanket Shield Module, a Trade-Off was made, and its contents are shown here. The outcome of this System Engineering approach has been formalized into Task Definition Forms whose contents are reported here. The Remote Handling strategy presented in this work will be tested in the near future both through Virtual Reality simulations and through prototype experiments.
Nardone A.
2012-09-01
Full Text Available The Electron Cyclotron (EC fast launcher for real time control experiments has been installed on FTU and characterized to be fully integrated in a real-time MHD control module under development. The launcher scheme is based on a two module system, symmetric with respect to the equatorial plane of FTU, with a front steering concept and the launched beams are real-time controllable both in poloidal and toroidal directions. Specific design parameters, defined by the FTU MHD dynamics (typically island size and q profile changes, are the beam dimensions with zooming capabilities, the steering range and mirror speed with the most demanding requirement on poloidal speed of the Steering Mirror (SM Δθ = 1° in 10 ms. A set of tests has been done to verify the system performance. High power tests of the launcher have been done on a 500 kA, 0.5·1020m−3 and 5.3 T plasma with 2·300 kW of EC power delivered to the plasma. The steering mechanism was tested under the automatic control system and showed a dynamic response in line with the requirements. Results of these tests will be presented in the paper.
Timpson, Erik J.; Engel, T. G.
2012-06-12
A pulse forming network (PFN), helical electromagnetic launcher (HEML), command module (CM), and calibration table (CT) were built and evaluated for the combined ability to calibrate an accelerometer. The PFN has a maximum stored nergy of 19.25 kJ bank and is fired by a silicon controlled rectifier (SCR), with appropriate safety precautions. The HEML is constructed out of G-10 fiberglass reinforced epoxy and is designed to accelerate a mass of 600 grams to a velocity of 10 meters per second. The CM is microcontroller-based running Arduino Software. The CM has a keypad input and 7 segment outputs of the PFN voltage and desired charging voltage. After entering a desired PFN voltage, the CM controls the charging of the PFN. When the two voltages are equal it sends a pulse to the SCR to fire the PFN and in turn, the HEML. The HEML projectile’s tip hits a target that is held by the CT. The CT consists of a table to hold the PFN and HEML, a vacuum chuck, air bearing, velocimeter and catch pot. The target is held with the vacuum chuck awaiting impact. After impact, the air bearing allows the target to fall freely so that the velocimeter can accurately read. A known acceleration is determined from the known change in velocity of the target. Thus, if an accelerometer was attached to the target, the measured value can be compared to the known value.
Guidelines for internal optics optimization of the ITER EC H and CD upper launcher
Moro, A.; Bruschi, A.; Figini, L.; Farina, D.; Platania, P.; Sozzi, C. [Istituto di Fisica del Plasma CNR, Euratom-ENEA Association, 20125 Milano (Italy); Chavan, R.; Goodman, T. P.; Krause, A.; Landis, J. D.; Sanchez Galan, F.; Toussaint, M. [Centre de Recherches en Physique des Plasmas, CRPP-EPFL, CH-1015 Lausanne (Switzerland); Henderson, M. A. [ITER Organization, 13108 Saint-Paul-lez-Durance (France); Saibene, G. [Fusion for Energy, Barcelona (Spain)
2014-02-12
The importance of localized injection of Electron Cyclotron waves to control Magneto-HydroDynamic instability is well assessed in tokamak physics and the set of four Electron Cyclotron (EC) Upper Launchers (UL) in ITER is mainly designed for this purpose. Each of the 4 ULs uses quasi-optical mirrors (shaping and planes, fixed and steerable) to redirect and focus 8 beams (in two rows, with power close to 1 MW per beam coming from the EC transmission lines) in the plasma region where the instability appears. Small beam dimensions and maximum beam superposition guarantee the necessary localization of the driven current. To achieve the goal of MHD stabilization with minimum EC power to preserve the energy confinement in the outer half of the plasma cross section, optimization of the quasi-optical design is required and a guideline of a strategy is presented. As a result of this process and following the guidelines indicated, modifications of the design (new mirrors positions, rotation axes and/or focal properties) will be proposed for the next step of an iterative process, including the mandatory compatibility check with the mechanical constraints.
Down-bore two-laser heterodyne velocimetry of an implosion-driven hypervelocity launcher
Hildebrand, Myles; Huneault, Justin; Loiseau, Jason; Higgins, Andrew J.
2017-01-01
The implosion-driven launcher uses explosives to shock-compress helium, driving well-characterized projectiles to velocities exceeding 10 km/s. The masses of projectiles range between 0.1 - 15 g, and the design shows excellent scalability, reaching similar velocities across different projectile sizes. In the past, velocity measurements have been limited to muzzle velocity obtained via a high-speed videography upon the projectile exiting the launch tube. Recently, Photon Doppler Velocimetry (PDV) has demonstrated the ability to continuously measure in-bore velocity, even in the presence of significant blow-by of high temperature helium propellant past the projectile. While a single laser system sampled at 40 GS/s with a 13 GHz detector/scope bandwidth is limited to 8 km/s, a two-laser PDV system is developed that uses two lasers operating near 1550 nm to provide velocity measurement capabilities up to 16 km/s with the same bandwidth and sampling rate. The two-laser PDV system is used to obtain a continuous velocity history of the projectile throughout the entire launch cycle. These internal ballistics trajectories are used to compare different advanced concepts aimed at increasing the projectile velocity to well beyond 10 km/s.
A new technology for production of high thickness carbon/carbon composites for launchers application
Albano, Marta; Delfini, Andrea; Pastore, Roberto; Micheli, Davide; Marchetti, Mario
2016-11-01
Carbon-Carbon (C/C) composites are known for their extraordinary stability and excellent mechanical properties, almost unchanged at high temperatures. Among the several advanced applications, C/C based materials can be used in engines as nozzle throat section for launchers. In particular, the main feature for such employment is the material high resistance in extreme thermal environment. On the other hand, large-size items are required for this kind of purposes, thus introducing criticalities in terms of material uniformity and final overall properties. Up to now, there no standard for the production of high thickness C/C structures. In this paper a novel manufacturing method is analyzed, following each phase of the process, from the carbon fiber preform design and preparation to the carbon densification by chemical vapor infiltration method. Five preforms of large dimensions with different characteristics have been manufactured and infiltrated. The realized prototypes have been then analyzed by means of mechanical, physical and morphological tests. Aim of the results of this preliminary work is to establish a set of guidelines for a well-defined high thickness C/C production method.
Cornette, James B.; Sterrett, John D.; Lippert, Jack R.; Williams, Robert W.
1989-08-01
The preliminary design of the battery power supply (BPS) was reported to the 6th IEEE Pulsed Power conference. In 1987, the final design was completed, assembled, and sequentially verified during approximately 1750 operational verification tests. These experiments consisted of single string verifications at 1000 amperes to a system discharge of 2,150,000 amperes. Final system design is very similar to the preliminary design previously presented. System fabrication is complete and at the present time consists of 858, 16 battery series strings resulting in 13,728 operational batteries. The final switching design has evolved into several levels of redundancy at varying current levels. These include 36 pneumatic, 100,000 ampere switches that control 24, 16 battery strings in parallel. These switches are used for the primary make and break of system current to charge the inductor. There are also 18 pneumatic crowbar switches at the 24 string level that are used to short the inductor from the BPS prior to system opening. At the string level there are 2000 ampere dc contactors that are used as a secondary current break and to pre-set the BPS in the appropriate parallel/series configuration prior to a discharge sequence. Explosively driven opening and closing switches are also employed at the interface junction to any Hypervelocity launcher test article.
New advanced launcher for lower hybrid current drive on Tore Supra
Bibet, Ph.; Agarici, G.; Chantant, M.; Cordier, J.J.; Deck, C.; Doceul, L.; Durocher, A.; Ekedahl, A.; Froissard, Ph.; Garguiolo, L.; Garampon, L.; Goniche, M.; Hertout, P.; Kazarian, F.; Lafon, D.; Portafaix, C.; Rey, G.; Samaille, F.; Surle, F.; Tonon, G
2000-11-01
A new actively cooled advanced launcher is being built for Tore Supra LHCD to inject 4 MW during 1000 s at 3.7 GHz, at a power density of 25 MW/m{sup 2} (a conservative value observed in Tore Supra experiments). It is made from an array of 6x48 active and 6x9 passive waveguides. The design uses technologies which are relevant for a next step machine such that it can: (i) withstand a plasma radiated flux of 0.15 MW/m{sup 2}; (ii) radiate power with spectra having peak N// values of 2.02{+-}0.35; (iii) withstand a total torque of 8.6 10{sup 4} N m during disruptions; (iv) allow an antenna 20 cm radial stroke adjustable in real time, (v) withstand a convected power flux of 10 MW/m{sup 2} on its guard limiter made of CFC tiles. A prototype of each new component of this antenna has been tested successfully at the nominal power with a pulse length of 1000 s.
Reliability and Quality Assurance Experience in Launcher Hold and Release System used in GSLV
J. Singaravelu
2002-01-01
Full Text Available The launcher hold and release system (LHRS was successfully used, for the first time, for GSLV-DI mission after thorough test and evaluation, in line with reliability and quality assurance (R&QA requirements. Various R&QA techniques are applied to make LHRS failure-free. Failure mode effect and criticality analysis (FMECA was used as a tool for identifying critical failure modes. Single-point failure modes (SPFMs identified from FMECA are strengthened by design modifications and the same are verified by testing. Testing philosophy is tailored to have more number of tests at the system level. Capability demonstration tests and failure mode simulation tests were carried out during system qualification phase. Acceptance tests are done on the flight hardware at launch pad to demonstrate better confidence on the system. This paper illustrates how R&QA techniques complimented and added value at different stages in the development cycle of LHRS, by means of few case studies. Testing methodologies adopted and problems encountered during the development and qualification phases are described in brief. Various problems surfaced during preparation for flight are also discussed.
Design for robustness using the μ-synthesis applied to launcher attitude and vibration control
Morita, Yasuhiro; Goto, Shinichi
2008-01-01
The M-V launch vehicle of Japan Aerospace Exploration Agency (JAXA) has successfully injected Japan's fifth X-ray space telescope "SUZAKU" into its low earth orbit in this past July. The attitude and vibration control algorithm of the M-V rocket used to be highlighted by its H∞ robust stability since its first flight conducted in 1997. Beyond this, its robustness character has been further enhanced using the μ-synthesis approach to get better robust characteristics not only in stability but in tracking performance under uncertainty of the system dynamics. The performance has been validated by the latest back-to-back successful flights of the vehicle: in May 2003 to directly inject Japan's first asteroid sample return spaceship "HAYABUSA" into the planned inter-planetary trajectory and in this past July to launch the telescope. The μ-synthesis has been applied for the first time ever for Japan's launcher control beyond the reliable H∞ design. The plant dynamics has an extremely high-order and unstable characteristics, thus the standard μ-synthesis format cannot be directly applied. The paper gives a unique methodology to apply the theory to such a real high-order complicated system.
Design status of the ITER ECRH upper launcher mm-wave system
Landis, J.-D. [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association Euratom-Confederation Suisse, 1015 Lausanne (Switzerland)], E-mail: jean-daniel.landis@epfl.ch; Chavan, R.; Bertizzolo, R.; Collazos, A.; Dolizy, F.; Felici, F.; Sanchez, F. [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association Euratom-Confederation Suisse, 1015 Lausanne (Switzerland); Henderson, M. [ITER, Organization, Cadarache Centre, Saint Paul Lez Durance (France)
2009-06-15
The purpose of the ITER electron cyclotron resonance heating (ECRH) upper launcher (UL), or antennae will be to provide localised current drive by accurately directing mm-wave beams up to 2MW, out of the four allocated upper port plugs, at chosen rational magnetic flux surfaces in order to stabilise neoclassical tearing modes (NTMs). This paper will present an overview of the UL, with emphasis on the mm-wave components. The mm-wave layout includes corrugated waveguide sections and a quasi-optical path with both focusing mirrors and plane steering mirrors. One of the essential components of the UL is the Steering Mechanism Assembly (SMA), providing variable poloidal injection angles fulfilling high deposition accuracy requirements at the plasma location. The Actuator principle and rotor bearings are frictionless and backlash free, avoiding tribological difficulties such as stickslip and seizure. The underlying working principle is the use of mechanically compliant structures. Validation and proof testing of the steering principle is achieved with an uncooled first prototype demonstrator. A second prototype is currently being manufactured, comprising the functionalities needed for the ITER compatible system such as water cooling and high power mm-wave compatibility. In order to perform the fatigue tests of the actuator bellows, a test facility has been built, under ITER-like vacuum and temperature working conditions. Results of the cyclic fatigue tests are compared to the various manufacturer standards and codes, combining stress and strain controlled material fatigue properties.
Analysis of induction-type coilgun performance based on cylindrical current sheet model
He, J.L.; Levi, E.; Zabar, Z.; Birenbaum, L.; Naot, Y. (Polytechnic Univ., Brooklyn, NY (United States))
1991-01-01
This paper presents a method based on a cylindrical current sheet model for the analysis and design of induction-type coilguns. The paper starts with a derivation of closed-form formulas which relate the dimensions of the gun to the performance expressed in terms of propulsive and local maximum forces on the projectile, power factor and efficiency of the system, thermal stress of the projectile armature, distributions of the flux density around the launcher, and the system parameters in a multisection coilgun. The paper ends with a numerical example.
Analysis of induction-type coilgun performance based on cylindrical current sheet model
He, J. L.; Levi, E.; Zabar, Z.; Birenbaum, L.; Naot, Y.
1991-01-01
A method which is based on a cylindrical current sheet model for the analysis and design of induction-type coilguns is presented. The work starts with a derivation of closed-form formulas which relate the dimensions of the gun to the performance expressed in terms of propulsive and local maximum forces on the projectile, power factor and efficiency of the system, thermal stress of the projectile armature, distributions of the flux density around the launcher, and the system parameters in a multisection coilgun. A numerical example is given.
The report documents a series of seminars at Rome Air Development Center with the content equivalent to an intense course in Linear Systems . Material...is slanted toward the practicing engineer and introduces some of the fundamental concepts and techniques for analyzing linear systems . Techniques for
Stoll, R R
1968-01-01
Linear Algebra is intended to be used as a text for a one-semester course in linear algebra at the undergraduate level. The treatment of the subject will be both useful to students of mathematics and those interested primarily in applications of the theory. The major prerequisite for mastering the material is the readiness of the student to reason abstractly. Specifically, this calls for an understanding of the fact that axioms are assumptions and that theorems are logical consequences of one or more axioms. Familiarity with calculus and linear differential equations is required for understand
ITER ECRH Upper Launcher: Test plan for qualification of the Diamond Torus Window Prototype III
Schreck, Sabine, E-mail: sabine.schreck@kit.edu [Karlsruhe Institute of Technology, Institute for Applied Materials, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Aiello, Gaetano; Meier, Andreas; Strauss, Dirk [Karlsruhe Institute of Technology, Institute for Applied Materials, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Gagliardi, Mario; Saibene, Gabriella [F4E, Antennas and Plasma Engineering, Josep Pla 2, Torres Diagonal Litoral B3, 08019 Barcelona (Spain); Scherer, Theo [Karlsruhe Institute of Technology, Institute for Applied Materials, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)
2016-11-01
Highlights: • A qualification program for the ITER diamond torus window is being developed. • The testing program for the qualification of the bare diamond disk is defined. • First qualification tests show a very good quality of the diamond disk prototypes. - Abstract: The diamond window is part of the electron cyclotron heating upper launcher system for ITER. Together with the isolation valve it constitutes the primary vacuum boundary and it also acts as first tritium barrier. Therefore the window is classified as Safety/Protection Important Component (SIC/PIC) with the nuclear safety function “confinement”. As the diamond window unit is not entirely covered by standard codes, an ad-hoc qualification program needs to be defined, including analysis, prototyping and testing. In the framework of a contract with F4E, the test program for a diamond window prototype is being developed with the aim to prove its operability for normal, accidental and incidental conditions as identified in the ITER load specifications. Tests range from dielectric loss measurements for the bare Chemical Vapour Deposition (CVD) diamond disk up to mechanical and vacuum tests for the complete window assembly. Finally mm-wave properties have to be characterized for the complete window. A clear definition of the testing requirements and of the acceptance criteria is necessary as well as a complete documentation of the process. This paper will present the development of the test plan for a window prototype, which is currently under manufacturing. First tests are directed to the characterization of the bare diamond disk with a focus on its dielectric properties.
Searle, Shayle R
2012-01-01
This 1971 classic on linear models is once again available--as a Wiley Classics Library Edition. It features material that can be understood by any statistician who understands matrix algebra and basic statistical methods.
Solow, Daniel
2014-01-01
This text covers the basic theory and computation for a first course in linear programming, including substantial material on mathematical proof techniques and sophisticated computation methods. Includes Appendix on using Excel. 1984 edition.
Berberian, Sterling K
2014-01-01
Introductory treatment covers basic theory of vector spaces and linear maps - dimension, determinants, eigenvalues, and eigenvectors - plus more advanced topics such as the study of canonical forms for matrices. 1992 edition.
Liesen, Jörg
2015-01-01
This self-contained textbook takes a matrix-oriented approach to linear algebra and presents a complete theory, including all details and proofs, culminating in the Jordan canonical form and its proof. Throughout the development, the applicability of the results is highlighted. Additionally, the book presents special topics from applied linear algebra including matrix functions, the singular value decomposition, the Kronecker product and linear matrix equations. The matrix-oriented approach to linear algebra leads to a better intuition and a deeper understanding of the abstract concepts, and therefore simplifies their use in real world applications. Some of these applications are presented in detailed examples. In several ‘MATLAB-Minutes’ students can comprehend the concepts and results using computational experiments. Necessary basics for the use of MATLAB are presented in a short introduction. Students can also actively work with the material and practice their mathematical skills in more than 300 exerc...
郭亚军; 马大为; 王晓峰; 乐贵高
2011-01-01
An adaptive backstepping sliding mode control approach is introduced to control the pitch motion of a rocket launcher. Its control law is proposed to guarantee that the control system is ultimately bounded in a Lyapunov sense and make the servo system track the instruction of reference position globally and asymptotically. In addition, the sliding mode control can restrain the effects of parameter uncertainties and external disturbance. The functions of adaptive mechanism and sliding mode control are analyzed through the simulation in the different conditions. The simulation results illustrate that the method is applicable and robust.
Cornette, J.B.
1992-02-01
Candidate pulsed power systems for electromagnetic launchers constitute two broad categories: rotating machinery and non-rotating devices. Rotating machinery for this purpose is under development at several industrial and educational institutions around the world. Non-rotating hardware includes capacitors, batteries, and inductors. These, too, are the subject of research programs, but as yet, are much larger than rotating supplies of equal power and energy capability. In 1988, system studies identified several attractive pulsed power systems for electromagnetic launchers. Battery charged capacitor pulsed power systems were among those identified as promising for electromagnetic launcher systems. The basic equations governing the battery charging capacitor sequence, and the capacitor discharge into an electromagnetic launcher are the subject of this report. A battery charged capacitor system powering an electromagnetic launcher has also been built and tested. This experiment not only validates the system concept with presently available hardware, but can be used to establish a baseline for evaluation of future systems when technology in capacitor and battery power and energy densities improve.
韦克康; 郑琼林; 文晓燕; 王琛琛
2011-01-01
Measuring real-time traction motor speeds efficiently is the basis of achieving high performance traction control of Electric Multiple Units (EMUs). In this paper ,the speed estimation methods for the induction motor and the measuring principle of the gear speed sensor are introduced. Then, a new speed estimation method based on T-method measuring is proposed for the induction motor used in EMUs. It works very well, especially in the low-speed range and dynamic process of speed regulation, which removes measuring delay brought by the low resolution ratio and achieves speed estimation with an accuracy independent of parameter variations of the traction motor. The accuracy of rotor flux orientation is also improved greatly through speed estimation. Finally, taking the traction motor of EMU Xianfeng as an example, simulation and tests are made and the results demonstrate the rationality of the new method.%如何有效实时检测牵引电机的速度信息是实现动车组高性能牵引控制的基础.本文介绍用于动车组速度的齿轮速度传感器的测速原理,在此基础上,提出一种基于线性插值的电动车组用异步牵引电机转速估计的方法.该方法在低速区和转速调节的动态过程中效果显著,有效克服速度传感器低分辨率带来的测最延时问题,并且转速估计的准确性不受牵引电机参数变化的影响.通过对转速的估计,间接矢量控制中转子磁场定向的准确度也明显提高.本文以国产先锋号电动车组的牵引电机控制为例,利用本文方法进行仿真和实验研究,仿真和实验结果验证了该方法的准确性.
Olive, David J
2017-01-01
This text covers both multiple linear regression and some experimental design models. The text uses the response plot to visualize the model and to detect outliers, does not assume that the error distribution has a known parametric distribution, develops prediction intervals that work when the error distribution is unknown, suggests bootstrap hypothesis tests that may be useful for inference after variable selection, and develops prediction regions and large sample theory for the multivariate linear regression model that has m response variables. A relationship between multivariate prediction regions and confidence regions provides a simple way to bootstrap confidence regions. These confidence regions often provide a practical method for testing hypotheses. There is also a chapter on generalized linear models and generalized additive models. There are many R functions to produce response and residual plots, to simulate prediction intervals and hypothesis tests, to detect outliers, and to choose response trans...
Sahai, Vivek
2013-01-01
Beginning with the basic concepts of vector spaces such as linear independence, basis and dimension, quotient space, linear transformation and duality with an exposition of the theory of linear operators on a finite dimensional vector space, this book includes the concept of eigenvalues and eigenvectors, diagonalization, triangulation and Jordan and rational canonical forms. Inner product spaces which cover finite dimensional spectral theory and an elementary theory of bilinear forms are also discussed. This new edition of the book incorporates the rich feedback of its readers. We have added new subject matter in the text to make the book more comprehensive. Many new examples have been discussed to illustrate the text. More exercises have been included. We have taken care to arrange the exercises in increasing order of difficulty. There is now a new section of hints for almost all exercises, except those which are straightforward, to enhance their importance for individual study and for classroom use.
Edwards, Harold M
1995-01-01
In his new undergraduate textbook, Harold M Edwards proposes a radically new and thoroughly algorithmic approach to linear algebra Originally inspired by the constructive philosophy of mathematics championed in the 19th century by Leopold Kronecker, the approach is well suited to students in the computer-dominated late 20th century Each proof is an algorithm described in English that can be translated into the computer language the class is using and put to work solving problems and generating new examples, making the study of linear algebra a truly interactive experience Designed for a one-semester course, this text adopts an algorithmic approach to linear algebra giving the student many examples to work through and copious exercises to test their skills and extend their knowledge of the subject Students at all levels will find much interactive instruction in this text while teachers will find stimulating examples and methods of approach to the subject
Dynamic Numerical Emulation of A New Electromagnetic Launcher%螺旋线圈型电磁发射器有限元动态数值仿真
欧阳建明; 刘振祥; 杨丽佳; 沈志; 杨栋; 蒋雅琴
2011-01-01
A new electromagnetic launcher was designed based on the basic structure of helical coil electromagnetic launchers (HCEL).The moving processes of helical coil electromagnetic launchers (HCEL) with coil armatures and ferromagnetic armatures were analyzed numerically.Analyzed the force and velocity versus time of the two armatures contrastively.%基于有限元方法,对螺旋线圈型电磁发射器的动态发射过程进行了数值分析.螺旋线圈型电磁发射器弹丸可采用线圈弹丸和铁磁弹丸,对比分析了两种弹丸运动过程中受力和速度随时间的变化关系.
Allenby, Reg
1995-01-01
As the basis of equations (and therefore problem-solving), linear algebra is the most widely taught sub-division of pure mathematics. Dr Allenby has used his experience of teaching linear algebra to write a lively book on the subject that includes historical information about the founders of the subject as well as giving a basic introduction to the mathematics undergraduate. The whole text has been written in a connected way with ideas introduced as they occur naturally. As with the other books in the series, there are many worked examples.Solutions to the exercises are available onlin
Repetitive energy transfer from an inductive energy store
Honig, E.M.
1984-01-01
The theoretical and experimental results of a research program aimed at finding practical ways to transfer energy repetitively from an inductive energy store to various loads are discussed. The objectives were to investigate and develop the high power opening switches and transfer circuits needed to enable high-repetition-rate operation of such systems, including a feasibility demonstration at a current level near 10 kA and a pulse repetition rate of 1-10 kpps with a 1-ohm load. The requirements of nonlinear, time-varying loads, such as the railgun electromagnetic launcher, were also addressed. Energy storage capability is needed for proper power conditioning in systems where the duty factor of the output pulse train is low. Inductive energy storage is attractive because it has both a high energy storage density and a fast discharge capability. By producing a pulse train with a peak power of 75 MW at a pulse repetition rate of 5 kpps in a one-ohm load system, this research program was the first to demonstrate fully-controlled, high-power, high-repetition-rate operation of an inductive energy storage and transfer system with survivable switches. Success was made possible by using triggered vacuum gap switches as repetitive, current-zero opening switches and developing several new repetitive transfer circuits using the counterpulse technique.
ITER ECRH upper launcher torus diamond window – Prototyping, testing and qualification
Schreck, Sabine, E-mail: sabine.schreck@kit.edu [Karlsruhe Institute of Technology, Institute for Applied Materials, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Aiello, Gaetano; Meier, Andreas; Strauss, Dirk [Karlsruhe Institute of Technology, Institute for Applied Materials, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany); Ikeda, Ryosuke; Oda, Yasuhisa; Sakamoto, Keishi; Takahashi, Koji [Japan Atomic Energy Agency (JAEA), Plasma Heating Technology Group, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan); Scherer, Theo [Karlsruhe Institute of Technology, Institute for Applied Materials, Association KIT-EURATOM, P.O. Box 3640, D-76021 Karlsruhe (Germany)
2015-10-15
Highlights: • The diamond window prototype shows a very good transmission capability during high power RF experiments. • An ad-hoc qualification programme for the diamond torus window is being developed (contract between KIT and F4E). • The window design has been updated focused on its mechanical integrity and manufacturing aspects. - Abstract: The diamond window assembly is part of the ITER primary vacuum boundary and acts as the first tritium barrier and therefore it is classified as Safety/Protection Important Component (SIC/PIC). It consists of an ultra-low loss CVD diamond disk mounted in a system of metallic parts (copper/steel) and has to fulfil adequate transmission capability for high power mm-waves. High power RF experiments with a 1st window prototype had shown parasitic heating due to small gaps in the housing. After a design optimization directed to the mm-wave properties, the parasitic excitations of oscillations have been avoided in a 2nd prototype. This one is equipped with inserted waveguide structures, which cover gaps in the metallic structure of the window housing. From high power RF-measurements with a 0.86 MW/100 s pulse a loss tangent of 7.1 × 10{sup −6} could be estimated, corresponding to an increase of temperature of only 120 mK between inlet and outlet of the cooling system. The diamond window assemblies cannot be entirely covered by codes and standards. To comply with the French safety regulations, instead an ad-hoc qualification programme is required, being developed in the framework of a contract between KIT and F4E. A new prototype (3rd) will be built, which is designed to fit to the single HELICOFLEX sealed waveguide structures of the ex-vessel mm-system of the EC upper launcher (UL). The testing programme ranges from mechanical to vacuum tests up to dielectric loss measurements at low and high power. A clear definition of the testing requirements and of the acceptance criteria is necessary as well as a complete
Tung, L S; Post, R F; Martinez-Frias, J
2001-06-27
The Inductrack magnetic levitation system, developed at the Lawrence Livermore National Laboratory, was studied for its possible use for launching rockets. Under NASA sponsorship, a small model system was constructed at the Laboratory to pursue key technical aspects of this proposed application. The Inductrack is a passive magnetic levitation system employing special arrays of high-field permanent magnets (Halbach arrays) on the levitating cradle, moving above a ''track'' consisting of a close-packed array of shorted coils with which are interleaved with special drive coils. Halbach arrays produce a strong spatially periodic magnetic field on the front surface of the arrays, while canceling the field on their back surface. Relative motion between the Halbach arrays and the track coils induces currents in those coils. These currents levitate the cradle by interacting with the horizontal component of the magnetic field. Pulsed currents in the drive coils, synchronized with the motion of the carrier, interact with the vertical component of the magnetic field to provide acceleration forces. Motional stability, including resistance to both vertical and lateral aerodynamic forces, is provided by having Halbach arrays that interact with both the upper and the lower sides of the track coils. At present, a 7.8 meter track composed of drive and levitation coils has been built and the electronic drive circuitry performs as designed. A 9 kg cradle that carries the Halbach array of permanent magnets has been built. A mechanical launcher is nearly complete which will provide an initial cradle velocity of 9 m/s into the electronic drive section. We have found that the drag forces from the levitation coils were higher than in our original design. However, measurements of drag force at velocities less than 1 m/s are exactly as predicted by theory. Provided here are recommended design changes to improve the track's performance so that a final velocity of 40
周晓霞
2014-01-01
开发一种应用先进的直线电机驱动技术的新型自动化立体停车库，对于提高停车的地面利用率和存取速度，降低立体停车系统的故障率，提高其可靠性，具有关键作用。本文介绍了基于贝加莱工控系统的扁平型直线感应电动机驱动立体停车库解决方案，首先论述了三相扁平单边型直线感应电动机驱动的基本原理和立体停车库的布置及机电设备，重点描述了该类立体停车库自动控制系统的构成、主要功能和特点以及载车平板的平移和升降驱动，最后总结了直线电机驱动立体停车方案的优点。%To develop a kind of new type three-dimensional automation garage by using advanced linear motor driving technology is a key factor for increasing parking ground utilization rate and speed of saving and taking cars, reducing failure rate of three-dimensional parking system and improving its reliability. A solution of three-dimensional garage with the flat-type linear induction motor driving based on B&R’s industrial control system is introduced in this paper. Firstly, the fundamental principles of the three-phase flat single sided linear induction motor driving are introduced, as well as the arrangement and related electro-mechanical equipment.Then the composition, main functions and characteristics of such stereo-garage’s automatic control system as well as the planar shift and lifting driving of the car loading plate are elaborated in details. Finally, the advantages of the linear motor driving stereo-parking scheme are summarized.
Backstepping Sliding Mode Control for Induction Motor
Othmane Boughazi
2014-12-01
Full Text Available This work treats the modeling and simulation of non-linear system behavior of an induction motor using backstepping sliding mode control. First, the direct field oriented control IM is derived. Then, a sliding for direct field oriented control is proposed to compensate the uncertainties, which occur in the control.Finally, the study of Backstepping sliding controls strategy of the induction motor drive. Our non linear system is simulated in MATLAB SIMULINK environment, the results obtained illustrate the efficiency of the proposed control with no overshoot, and the rising time is improved with good disturbances rejections comparing with the classical control law.
Karloff, Howard
1991-01-01
To this reviewer’s knowledge, this is the first book accessible to the upper division undergraduate or beginning graduate student that surveys linear programming from the Simplex Method…via the Ellipsoid algorithm to Karmarkar’s algorithm. Moreover, its point of view is algorithmic and thus it provides both a history and a case history of work in complexity theory. The presentation is admirable; Karloff's style is informal (even humorous at times) without sacrificing anything necessary for understanding. Diagrams (including horizontal brackets that group terms) aid in providing clarity. The end-of-chapter notes are helpful...Recommended highly for acquisition, since it is not only a textbook, but can also be used for independent reading and study. —Choice Reviews The reader will be well served by reading the monograph from cover to cover. The author succeeds in providing a concise, readable, understandable introduction to modern linear programming. —Mathematics of Computing This is a textbook intend...
Schürmann, Carsten; Sarnat, Jeffrey
2009-01-01
Programming languages theory is full of problems that reduce to proving the consistency of a logic, such as the normalization of typed lambda-calculi, the decidability of equality in type theory, equivalence testing of traces in security, etc. Although the principle of transfinite induction...... an induction principle that combines the comfort of structural induction with the expressive strength of transfinite induction. Using lexicographic path induction, we give a consistency proof of Martin-Löf’s intuitionistic theory of inductive definitions. The consistency of Heyting arithmetic follows directly...
Inductive Monitoring System (IMS)
National Aeronautics and Space Administration — IMS: Inductive Monitoring System The Inductive Monitoring System (IMS) is a tool that uses a data mining technique called clustering to extract models of normal...
Bourlès, Henri
2013-01-01
Linear systems have all the necessary elements (modeling, identification, analysis and control), from an educational point of view, to help us understand the discipline of automation and apply it efficiently. This book is progressive and organized in such a way that different levels of readership are possible. It is addressed both to beginners and those with a good understanding of automation wishing to enhance their knowledge on the subject. The theory is rigorously developed and illustrated by numerous examples which can be reproduced with the help of appropriate computation software. 60 exe
Byron, S.
1985-03-01
The low pressure gas-filled thyratron is scalable in the long dimension. Internally the tube is formed as a tetrode, with an auxiliary grid placed between the cathode and the control grid. A dc or pulsed power source drives the auxiliary grid both to insure uniform cathode emission and to provide a grid-cathode plasma prior to commutation. The high voltage holdoff structure consists of the anode, the control grid and its electrostatic shielding baffles, and a main quartz insulator. A small gas flow supply and exhaust system is used that eliminates the need for a hydrogen reservoir and permits other gases, such as helium, to be used. The thyratron provides a low inductance, high current, long lifetime switch configuration: useful for switch-on applications involving large scale lasers and other similar loads that are distributed in a linear geometry.
Gessner, R.; Aiello, G.; Grossetti, G.; Meier, A.; Ronden, D.; Spaeh, P.; Scherer, T.; Schreck, S.; Strauss, D.; Vaccaro, A.
2013-01-01
The final design of the structural system for the ITER EC H&CD upper launcher is in progress. Many design features of the preliminary design are under revision with the aim to achieve the built-to-print-status. This paper deals with design and analysis of a bolted joint for the Blanket Shield Mo
Denecker, Marc; Ternovska, Eugenia
2004-01-01
Temporal reasoning has always been a major test case for knowledge representation formalisms. In this paper, we develop an inductive variant of the situation calculus in ED-logic, classical logic extended with inductive definitions. This logic has been proposed recently and is an extension of classical logic. It allows for a uniform representation of various forms of definitions, including monotone inductive definitions and non-monotone forms of inductive definitions such as iterated inductio...
Hypotheses and Inductive Predictions
ROMEYN, J.-W.
2008-01-01
ABSTRACT. This paper studies the use of hypotheses schemes in generating inductive predictions. After discussing Carnap–Hintikka inductive logic, hypotheses schemes are defined and illustrated with two partitions. One partition results in the Carnapian continuum of inductive methods, the other resul
Hypotheses and Inductive Predictions
ROMEYN, J.-W.
2008-01-01
ABSTRACT. This paper studies the use of hypotheses schemes in generating inductive predictions. After discussing Carnap–Hintikka inductive logic, hypotheses schemes are defined and illustrated with two partitions. One partition results in the Carnapian continuum of inductive methods, the other resul
Inductive Reasoning and Writing
Rooks, Clay; Boyd, Robert
2003-01-01
Induction, properly understood, is not merely a game, nor is it a gimmick, nor is it an artificial way of explaining an element of reasoning. Proper understanding of inductive reasoning--and the various types of reasoning that the authors term inductive--enables the student to evaluate critically other people's writing and enhances the composition…
Boldea, Ion
2002-01-01
Often called the workhorse of industry, the advent of power electronics and advances in digital control are transforming the induction motor into the racehorse of industrial motion control. Now, the classic texts on induction machines are nearly three decades old, while more recent books on electric motors lack the necessary depth and detail on induction machines.The Induction Machine Handbook fills industry's long-standing need for a comprehensive treatise embracing the many intricate facets of induction machine analysis and design. Moving gradually from simple to complex and from standard to
High average-power induction linacs
Prono, D.S.; Barrett, D.; Bowles, E.; Caporaso, G.J.; Chen, Yu-Jiuan; Clark, J.C.; Coffield, F.; Newton, M.A.; Nexsen, W.; Ravenscroft, D.
1989-03-15
Induction linear accelerators (LIAs) are inherently capable of accelerating several thousand amperes of /approximately/ 50-ns duration pulses to > 100 MeV. In this paper we report progress and status in the areas of duty factor and stray power management. These technologies are vital if LIAs are to attain high average power operation. 13 figs.
Characterizing Inductive and Capacitive Nonlinear RLC Circuits : A Passivity Test
García-Canseco, Eloísa; Jeltsema, Dimitri; Ortega, Romeo; Scherpen, Jacquelien M.A.
2004-01-01
Linear time-invariant RLC circuits are said to be inductive (capacitive) if the current waveform in sinusoidal steady-state has a negative (resp., positive) phase shift with respect to the voltage. Furthermore, it is known that the circuit is inductive (capacitive) if and only if the magnetic energy
邓江明; 陈特放; 唐建湘; 彭鹏; 居平
2015-01-01
论文提出一种针对单边直线感应电机(single-sided linear induction motors，SLIMs)的基于非线性负载扰动观测器的预测电流补偿控制策略。首先考虑到SLIM特有的动态端部效应的影响，通过跟踪补偿 M-轴电流分量来维持次级磁链 T-轴分量的恒定，而后在一次线性条件下，引入一阶离散泰勒级数对速度状态进行预测。另一方面将电机气隙变化与各类边端效应对电机推力输出的影响统一为系统受到负载扰动的影响，而应对此扰动，通过非线性扰动观测器，在预测前向控制通路增加了实时补偿控制量，借此提升整个预测控制系统的鲁棒特性。最后实验对所提算法的有效性进行了验证。%This paper presented a predictive current compensation control for a single-sided linear induction motor (SLIM)with nonlinear disturbance observers (NDOB). Firstly, to maintainT-axes secondary component flux linkage constant with consideration of the special dynamical eddy-effects (DEE) of the SLIM, a instantaneously tracing compensation ofM-axes current components was analyzed. Secondly, a predictive current scheme based on Taylor-discretization algorithm for promoting speed dynamical response and minimizing speed stable ripple was proposed. Finally, to deal with the external load coupled uncertainties and measured errors of unavoidable feedback control variables, i.e., current and speed, an effective kind of nonlinear disturbance observer was employed to estimate and feed forward compensate these load vibrations, so the robustness of the control system could be guaranteed. Experimental verification of the feasibility of the proposed predictive current compensation for a SLIM control system is performed.
The ringer - An efficient, high repetition rate circuit for electromagnetic launchers
Giorgi, D.; Helava, H.; Lindner, K.; Long, J.; Zucker, O.
1989-01-01
The Meatgrinder is an efficient, current-multiplying circuit which can be used to optimize the energy transfer to various electromagnetic gun configurations. The authors present a simple variant of the Meatgrinder circuit which permits a first-order current profiling into the gun and recovery of the inductive energy in the barrel at a high repetition rate. The circuit is basically a one-stage Meatgrinder which utilizes the ringing of the energy storage capacitor (less than 40 percent reversal) to perform the opening switch function and a solid-state diode as the crowbar switch between the two mutually coupled inductors. With resonant charging, this results in a completely passive, high-repetiton-rate electromagnetic-gun power supply. Since most of the barrel energy is recovered, a railgun with negligible muzzle flash can be realized.
LINEAR SYSTEMS AND LINEAR INTERPOLATION I
丁立峰
2001-01-01
he linear interpolation of linear system on a family of linear systems is introduced and discussed. Some results and examples on singly generated systems on a finite dimensional vector space are given.
唐建湘; 蒋新华; 邓江明; 陈特放
2015-01-01
With consideration of that some dynamical parameters in T-type equivalent circuit model (T-ECM) of a single-sided linear induction motor (SLIM) are nonlinear time- varying due to the unstable machine air-gap between primary and secondary sides specially when SLIM are applied in medium-low speed maglev traction system, two effective kind of states interconnected observers were employed to observe the d- and q-axis currents, secondary flux, mutual induction and secondary resistance variables. Since the dynamical parameters were bounded because of limite vibration of air-gap, the desired identification state deviations were asymptotically converged to zero as they satisfied the boundary Lyapunov periodic and aperodic stable conditions. With improved filter of observer, the distortion of primary current crossing end-effect zones could be effectively suppressed. The effectiveness of the proposed algorithm was verified by the experimental results.%单边直线感应电机(single-sided linear induction motor， SLIM)应用于中低速磁悬浮牵引系统时，因常导电磁悬浮气隙的波动而导致电机的实际机械气隙波动，从而引起电机动态等效电路相关控制参数的时变不稳定。对此该文分别将初级电流的d/q轴分量和考虑动态端部效应影响的等效互感、电阻参数作为状态观测量，进行了以内部状态互联的双观测器为基础的数学建模，同时根据观测器内部参数波动受限于局部有界的条件，从非周期和周期性时间波动两个方面进行了状态偏差的李雅普诺夫稳定性论证。另一方面，考虑到SLIM在初级电流场穿越横向铁心端部时出现的谐波扩散现象，对互联观测器内部的状态滤波器进行了改进设计，使得SLIM能直接穿越畸变电流扩散区运行而不影响电机控制系统的稳定性。实验部分对所提算法的有效性进行了验证。
Inductive Logic and Statistics
Romeijn, J. -W.
2009-01-01
This chapter concerns inductive logic in relation to mathematical statistics. I start by introducing a general notion of probabilistic induc- tive inference. Then I introduce Carnapian inductive logic, and I show that it can be related to Bayesian statistical inference via de Finetti's representatio
Tylka, Jonathan M.; Johnson, Kenneth L.; Henderson, Donald; Rodriguez, Karen
2012-01-01
Laser etched 300 series Stainless Steel Burst Disks (SSBD) ranging between 0.178 mm (0.007-in.) and 0.508mm (0.020-in.) thick were designed for use in a 17-caliber two-stage light gas launcher. First, a disk manufacturing method was selected using a combination of wire electrical discharge machining (EDM) to form the blank disks and laser etching to define the pedaling fracture pattern. Second, a replaceable insert was designed to go between the SSDB and the barrel. This insert reduced the stress concentration between the SSBD and the barrel, providing a place for the petals of the SSDB to open, and protecting the rifling on the inside of the barrel. Thereafter, a design of experiments was implemented to test and characterize the burst characteristics of SSBDs. Extensive hydrostatic burst testing of the SSBDs was performed to complete the design of experiments study with one-hundred and seven burst tests. The experiment simultaneously tested the effects of the following: two SSBD material states (full hard, annealed); five SSBD thicknesses 0.178, 0.254, 0.305, 0.381 mm (0.007, 0.010, 0.012, 0.015, 0.020-in.); two grain directions relative); number of times the laser etch pattern was repeated (varies between 5-200 times); two heat sink configurations (with and without heat sink); and, two barrel configurations (with and without insert). These tests resulted in the quantification of the relationship between SSBD thickness, laser etch parameters, and desired burst pressure. Of the factors investigated only thickness and number of laser etches were needed to develop a mathematical relationship predicting hydrostatic burst pressure of disks using the same barrel configuration. The fracture surfaces of two representative SSBD bursts were then investigated with a scanning electron microscope, one burst hydrostatically in a fixture and another dynamically in the launcher. The fracture analysis verified that both burst conditions resulted in a ductile overload failure
Caporaso, G J
2000-09-27
This presentation will be a broad survey of progress in induction technology over the past four years. Much work has been done on accelerators for hydrodynamic test radiography and other applications. Solid-state pulsers have been developed which can provide unprecedented flexibility and precision in pulse format and accelerating voltage for both ion and electron induction machines. Induction linacs can now be built which can operate with MHz repetition rates. Solid-state technology has also made possible the development of fast kickers for precision control of high current beams. New insulator technology has been developed which will improve conventional induction linacs in addition to enabling a new class of high gradient induction linacs.
Paul, Clayton R
2010-01-01
"Inductance is an unprecedented text, thoroughly discussing "loop" inductance as well as the increasingly important "partial" inductance. These concepts and their proper calculation are crucial in designing modern high-speed digital systems. World-renowned leader in electromagnetics Clayton Paul provides the knowledge and tools necessary to understand and calculate inductance." "With the present and increasing emphasis on high-speed digital systems and high-frequency analog systems, it is imperative that system designers develop an intimate understanding of the concepts and methods in this book. Inductance is a much-needed textbook designed for senior and graduate-level engineering students, as well as a hands-on guide for working engineers and professionals engaged in the design of high-speed digital and high-frequency analog systems."--Jacket.
Modelling Loudspeaker Non-Linearities
Agerkvist, Finn T.
2007-01-01
This paper investigates different techniques for modelling the non-linear parameters of the electrodynamic loudspeaker. The methods are tested not only for their accuracy within the range of original data, but also for the ability to work reasonable outside that range, and it is demonstrated...... that polynomial expansions are rather poor at this, whereas an inverse polynomial expansion or localized fitting functions such as the gaussian are better suited for modelling the Bl-factor and compliance. For the inductance the sigmoid function is shown to give very good results. Finally the time varying...
Linear Algebra and Smarandache Linear Algebra
Vasantha, Kandasamy
2003-01-01
The present book, on Smarandache linear algebra, not only studies the Smarandache analogues of linear algebra and its applications, it also aims to bridge the need for new research topics pertaining to linear algebra, purely in the algebraic sense. We have introduced Smarandache semilinear algebra, Smarandache bilinear algebra and Smarandache anti-linear algebra and their fuzzy equivalents. Moreover, in this book, we have brought out the study of linear algebra and ve...
Linear Algebra and Smarandache Linear Algebra
Vasantha, Kandasamy
2003-01-01
The present book, on Smarandache linear algebra, not only studies the Smarandache analogues of linear algebra and its applications, it also aims to bridge the need for new research topics pertaining to linear algebra, purely in the algebraic sense. We have introduced Smarandache semilinear algebra, Smarandache bilinear algebra and Smarandache anti-linear algebra and their fuzzy equivalents. Moreover, in this book, we have brought out the study of linear algebra and ve...
尹美方; 徐先勇; 李阳
2013-01-01
英国海军的“鱼狗”箱式鱼雷发射装置集储存与发射功能于一身，具有大大简化发射准备工作、根据实际情况模块化组合并通过机械形式集中施力等特点，近年来已逐渐成为鱼雷发射装置的研究热点。通过对英国“鱼狗”箱式鱼雷发射装置结构特点的详细分析，提出了我国舰用鱼雷发射装置应加强标准化、模块化设计，加强箱式发射装置、加强便捷化、加强新的发射技术等方面的研究，从而进一步提高舰艇快速反应能力，应对日益复杂的海洋战争。%British Navy′s kingfisher box-type torpedo launcher integrates storage function with launching function to greatly simplify the launching preparation. And it possesses the advantages of modular combination according to actual situation and exerting concentrated force on torpedo mechanically. Hence, it has become a hot spot in torpedo launcher research. In this paper, the structural characteristics of the kingfisher box-type torpedo launcher are analyzed. And sug-gestions about researches on shipborne torpedo launchers in China are offered, i.e. more attention should be paid to standardized and modular design, box-type torpedo launcher, convenient operation, and new launching technologies for gaining rapid reaction ability of warships.
Nassisi, V.; Delle Side, D.
2017-02-01
Nowadays, the employment and development of fast current pulses require sophisticated systems to perform measurements. Rogowski coils are used to diagnose cylindrical shaped beams; therefore, they are designed and built with a toroidal structure. Recently, to perform experiments of radiofrequency biophysical stresses, flat transmission lines have been developed. Therefore, in this work we developed a linear Rogowski coil to detect current pulses inside flat conductors. The system is first approached by means of transmission line theory. We found that, if the pulse width to be diagnosed is comparable with the propagation time of the signal in the detector, it is necessary to impose a uniform current as input pulse, or to use short coils. We further analysed the effect of the resistance of the coil and the influence of its magnetic properties. As a result, the device we developed is able to record pulses lasting for some hundreds of nanoseconds, depending on the inductance, load impedance, and resistance of the coil. Furthermore, its response is characterized by a sub-nanosecond rise time (˜100 ps). The attenuation coefficient depends mainly on the turn number of the coil, while the fidelity of the response depends both on the magnetic core characteristics and on the current distribution along the plane conductors.
Gessner, Robby, E-mail: robby.gessner@kit.edu [Karlsruhe Institute of Technology, Institute for Applied Materials, P.O. Box 3640, D-76021 Karlsruhe (Germany); Aiello, Gaetano; Grossetti, Giovanni; Meier, Andreas [Karlsruhe Institute of Technology, Institute for Applied Materials, P.O. Box 3640, D-76021 Karlsruhe (Germany); Ronden, Dennis [DIFFER – Dutch Institute for Fundamental Energy Physics, P.O. Box 1207, NL-3430 BE Nieuwegein (Netherlands); Spaeh, Peter; Scherer, Theo; Schreck, Sabine; Strauss, Dirk; Vaccaro, Alessandro [Karlsruhe Institute of Technology, Institute for Applied Materials, P.O. Box 3640, D-76021 Karlsruhe (Germany)
2013-10-15
Highlights: ► The BSM of the ECH Launcher is attached to the Launcher Main Frame by a bolted joint. ► The bolts were designed as “captive” in order to avoid their accidental removal from the joint. ► The bolted flange connection using two sets of 15 captive bolts (M22 × 2) placed along the sides. ► The captive bolt design is based on a concept that uses a dedicated spring ring, a standard spiral spring and a tensioning screw with two threads to secure the bolts in a form-locking stop. -- Abstract: The final design of the structural system for the ITER EC H and CD upper launcher is in progress. Many design features of the preliminary design are under revision with the aim to achieve the built-to-print-status. This paper deals with design and analysis of a bolted joint for the Blanket Shield Module with special perspective on Remote Handling capability. The BSM of the ECH Launcher is attached to the Launcher Main Frame by a bolted joint conceived so that in the Hot Cell Facility, RH maintenance can be performed on internal components. The joint must be capable to resist very high Electro-Magnetic loads from disruptions, while it has to sustain substantial thermal cycling during operation. Thus the need for a rigid and reliable design is essential. Beside the set of pre-stressed bolts the flanges were therefore equipped with additional shear keys to divert radial moments away from the bolts. Main focus of the work performed was the mechanical design of the joint and the assessment of the structural integrity with respect to the loads applied and its capability for maintenance by RH procedures. To fulfill a major aspect of the RH requirements, the bolts were designed as “captive” in order to avoid their accidental removal from the joint. The captive bolt design is based on a concept that uses a dedicated spring ring, a standard spiral spring and a tensioning screw with two threads to secure the bolts in a form-locking stop. The final approval phase of
Induction motor control design
Marino, Riccardo; Verrelli, Cristiano M
2010-01-01
""Nonlinear and Adaptive Control Design for Induction Motors"" is a unified exposition of the most important steps and concerns in the design of estimation and control algorithms for induction motors. A single notation and modern nonlinear control terminology is used to make the book accessible to readers who are not experts in electric motors at the same time as giving a more theoretical control viewpoint to those who are. In order to increase readability, the book concentrates on the induction motor, eschewing the much more complex and less-well-understood control of asynchronous motors. The
Properties of inductive reasoning.
Heit, E
2000-12-01
This paper reviews the main psychological phenomena of inductive reasoning, covering 25 years of experimental and model-based research, in particular addressing four questions. First, what makes a case or event generalizable to other cases? Second, what makes a set of cases generalizable? Third, what makes a property or predicate projectable? Fourth, how do psychological models of induction address these results? The key results in inductive reasoning are outlined, and several recent models, including a new Bayesian account, are evaluated with respect to these results. In addition, future directions for experimental and model-based work are proposed.
Electromagnetic induction in Australia
Lilley, F. E. M.
Electromagnetic induction at the terrestrial surface is a general and ubiquitous process. This note, which covers research on the subject in Australia, reflects the writer's own interest and refers particularly to induction by natural source fields in the period range of 1 minute to 1 day.Such source fields arise external to Earth, in the ionosphere and beyond, in the magnetosphere. The process of electromagnetic induction by these fields involves the flow through Earth of tens of thousands of amperes, over scale lengths of thousands of kilometers.
Making Mathematical Induction Meaningful
Hirsch, Christian R.
1976-01-01
The author argues that the "least number principle" (well-ordering for positive integers) is more intuitively acceptable to high school students than mathematical induction which can be derived from it. (SD)
Thermal kinetic inductance detector
Cecil, Thomas; Gades, Lisa; Miceli, Antonio; Quaranta, Orlando
2016-12-20
A microcalorimeter for radiation detection that uses superconducting kinetic inductance resonators as the thermometers. The detector is frequency-multiplexed which enables detector systems with a large number of pixels.
Fox, Robert L. (Inventor); Copeland, Carl E. (Inventor); Swaim, Robert J. (Inventor); Coultrip, Robert H. (Inventor); Johnston, David F. (Inventor); Phillips, W. Morris (Inventor); Johnson, Samuel D. (Inventor); Dinkins, James R. (Inventor); Buckley, John D. (Inventor)
1994-01-01
An induction heating device includes a handle having a hollow interior and two opposite ends, a wrist connected to one end of the handle, a U-shaped pole piece having two spaced apart ends, a tank circuit including an induction coil wrapped around the pole piece and a capacitor connected to the induction coil, a head connected to the wrist and including a housing for receiving the U-shaped pole piece, the two spaced apart ends of the pole piece extending outwardely beyond the housing, and a power source connected to the tank circuit. When the tank circuit is energized and a susceptor is placed in juxtaposition to the ends of the U-shaped pole piece, the susceptor is heated by induction heating due to magnetic flux passing between the two ends of the pole piece.
Adewole, A I A
2001-01-01
We show that the problem of unifying electromagnetism with gravity has an elegant solution in classical physics through the phenomenon of induction. By studying the way that induction leads to the formation of electromagnetic fields, we identify the classical field equations which the unified field must satisfy and a corresponding set of constitutive equations for the medium sustaining the field. The unification problem is then reduced to the problem of finding the exact form of these constitutive equations for different media by experiments.
Induction of the Proepicardium.
Maya-Ramos, Lisandro; Cleland, James; Bressan, Michael; Mikawa, Takashi
2013-09-01
The proepicardium is a transient extracardiac embryonic tissue that gives rise to the epicardium and a number of coronary vascular cell lineages. This important extracardiac tissue develops through multiple steps of inductive events, from specification of multiple cell lineages to morphogenesis. This article will review our current understanding of inductive events involved in patterning of the proepicardium precursor field, specification of cell types within the proepicardium, and their extension and attachment to the heart.
Induction of the Proepicardium
Takashi Mikawa
2013-07-01
Full Text Available The proepicardium is a transient extracardiac embryonic tissue that gives rise to the epicardium and a number of coronary vascular cell lineages. This important extracardiac tissue develops through multiple steps of inductive events, from specification of multiple cell lineages to morphogenesis. This article will review our current understanding of inductive events involved in patterning of the proepicardium precursor field, specification of cell types within the proepicardium and their extension and attachment to the heart.
Diophantine Correct Open Induction
Raffer, Sidney
2010-01-01
We give an induction-free axiom system for diophantine correct open induction. We relate the problem of whether a finitely generated ring of Puiseux polynomials is diophantine correct to a problem about the value-distribution of a tuple of semialgebraic functions with integer arguments. We use this result, and a theorem of Bergelson and Leibman on generalized polynomials, to identify a class of diophantine correct subrings of the field of descending Puiseux series with real coefficients.
1991-01-01
Induction heating technology, a magnetic non-deforming process, was developed by Langley researchers to join plastic and composite components in space. Under NASA license, Inductron Corporation uses the process to produce induction heating systems and equipment for numerous applications. The Torobonder, a portable system, comes with a number of interchangeable heads for aircraft repair. Other developments are the E Heating Head, the Toroid Joining Gun, and the Torobrazer. These products perform bonding applications more quickly, safely and efficiently than previous methods.
Nonlinear Control of Induction Motors: A Performance Study
Rasmussen, Henrik; Vadstrup, P.; Børsting, H.
1998-01-01
A novel approach to control of induction motors based on nonlinear state feedback has previously been presented by the authors. The resulting scheme gives a linearized input-output decoupling of the torque and the amplitude of the field. The proposed approach is used to design controllers...... for the field amplitude and the motor torque. The method is compared with the traditional Rotor Field Oriented Control method as regards variations in rotor resistance an magnetizing inductance...
Linearly constrained minimax optimization
Madsen, Kaj; Schjær-Jacobsen, Hans
1978-01-01
We present an algorithm for nonlinear minimax optimization subject to linear equality and inequality constraints which requires first order partial derivatives. The algorithm is based on successive linear approximations to the functions defining the problem. The resulting linear subproblems...
Kim, Bok Ki [Kwangwoon University, Seoul (Korea)
2001-02-01
The distribution of current in the conductors influenced by armature geometry and velocity is an important parameter for determining performance of an electromagnetic launcher(EML). The electric current in the early launching stage tends to flow on the outer surface of the conductors, resulting in very high local electric current density. However, the tendency for current to concentrate on the surface is driven by the velocity skin effect later in launching stage. The high current density produces high local heating and, consequently, increases armature wear which causes several defects on EML system. This paper investigates the effect of rail/armature geometry on current density distribution, launcher inductance gradient (L'), and contact force. Three geometrical parameters are used to characterize the railgun system. These are the ratio of contact length, relative position of contact leading edge to root trailing edge, and the ratio of rail overhang to the rail height. The distribution of current density, L',contact force between various configurations of the armature and the rail are analyzed and compared by using the EMAP3D program. (author). 6 refs., 9 figs., 3 tabs.
Reconditioning in synchronous operation with one parallel induction generator
Alana da Silva Magalhães
2016-11-01
Full Text Available The purpose of this paper is to compare mathematical modeling and practical bench in order to validate the electrical interactions between an induction generator and a synchronous generator. Two generators was connected to a common bus in steady state, subject to non-linear load. The results comparing modeling and bench tests show that the induction generator besides the active power increasing, has a better way for harmonic currents flowing in common bus. It was concluded that the induction generator repowering and attenuates current harmonic components present at the connection point, improving the network voltage profile.
Atkey, Robert; Ghani, Neil
2012-01-01
Dependently typed programming languages allow sophisticated properties of data to be expressed within the type system. Of particular use in dependently typed programming are indexed types that refine data by computationally useful information. For example, the N-indexed type of vectors refines lists by their lengths. Other data types may be refined in similar ways, but programmers must produce purpose-specific refinements on an ad hoc basis, developers must anticipate which refinements to include in libraries, and implementations must often store redundant information about data and their refinements. In this paper we show how to generically derive inductive characterisations of refinements of inductive types, and argue that these characterisations can alleviate some of the aforementioned difficulties associated with ad hoc refinements. Our characterisations also ensure that standard techniques for programming with and reasoning about inductive types are applicable to refinements, and that refinements can the...
Foundations of linear and generalized linear models
Agresti, Alan
2015-01-01
A valuable overview of the most important ideas and results in statistical analysis Written by a highly-experienced author, Foundations of Linear and Generalized Linear Models is a clear and comprehensive guide to the key concepts and results of linear statistical models. The book presents a broad, in-depth overview of the most commonly used statistical models by discussing the theory underlying the models, R software applications, and examples with crafted models to elucidate key ideas and promote practical model building. The book begins by illustrating the fundamentals of linear models,
赵建荣
2013-01-01
Three dimension design of launcher machine is built by Pro/E3.0—3D mechanic design software,and is analyzed on bearing loads, the stress and strain disciplinarian of launcher machine is acquired by the finite element software ANSYS Workbench. That the rigidity and intensity of launcher machine is up to the mustard is proved by stress magnitude and contour of strain.% 运用三维机械设计软件Pro/E3.0完成了炮架的三维造型，并对其进行受力分析，基于有限元分析软件AN⁃SYS Workbench得到了炮架的应力、应变规律.根据应力大小、应变云图证明炮架刚度、强度符合要求.
Feedback linearization of piecewise linear systems
Camlibel, Kanat; Ustoglu, Ilker
2005-01-01
One of the classical problems of nonlinear systems and control theory is feedback linearization. Its obvious motivation is that one can utilize linear control theory if the nonlinear system at hand is linearizable by feedback. This problem is well-understood for the smooth nonlinear systems. In the
Modeling Induction Motor Imbalances
Armah, Kabenla; Jouffroy, Jerome; Duggen, Lars
2016-01-01
This paper gives a study into the development of a generalized model for a three-phase induction motor that offers flexibility of simulating balanced and unbalanced parameter scenarios. By analyzing the interaction of forces within the motor, we achieve our main objective of deriving the system...
Learning and Inductive Inference
1982-07-01
is also a paradigm example of induction as discussed by philosophers ( Carnap , 1950). Data compression is of practical value for storage and...IBelser, A. 0. Hlolzman, and A. Kent (Eds.., Eneyclopedia of computer science and technology (Vol. II). New York: Marcel Dekker, 24 51. " Carnap , R. 1950
Dobbs, David E.
2009-01-01
The main purpose of this note is to present and justify proof via iteration as an intuitive, creative and empowering method that is often available and preferable as an alternative to proofs via either mathematical induction or the well-ordering principle. The method of iteration depends only on the fact that any strictly decreasing sequence of…
Teaching Mathematical Induction I.
Dubinsky, Ed
1986-01-01
A novel approach to teaching mathematical induction was used, based on a Piagetian theory of learning abstract mathematical concepts in which the learner uses reflective abstraction to construct new schemas out of old ones. Computer experiences are used to induce students to make the appropriate reflective abstractions. (MNS)
Hathaway, Dan
2011-01-01
Here is a technique for proving the fundamental theorems of analysis that provides a unified way to pass from local properties to global properties on the real line, just as ordinary induction passes from local implication (if true for "k", the theorem is true for "k" + 1) to a global conclusion in the natural numbers.
Training in Inductive Reasoning.
Tomic, Welko
This study investigated the effects of K. J. Klauer's (1989) inductive reasoning training program of teaching children. Effects of training and the range of transfer of the training were assessed. The subjects were 34 third-grade Dutch children of average ability, matched on age, sex, and IQ. Children from the training condition (N=17) received…
Decision Procedures for Proving Inductive Theorems without Induction
Aoto, Takahito; Stratulat, Sorin
2014-01-01
International audience; Automated inductive reasoning for term rewriting has been extensively studied in the literature. Classes of equations and term rewriting systems (TRSs) with decidable inductive validity have been identified and used to automatize the inductive reasoning. We give procedures for deciding the inductive validity of equations in some standard TRSs on natural numbers and lists. Contrary to previous decidability results, our procedures can automatically decide without involvi...
Mutation induction by ion beams in plants
Tanaka, Atsushi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment
2001-03-01
The effect of ion beams such as C, He, and Ne ions was investigated on the mutation induction in plants with the expectation that ion beams of high linear energy transfer (LET) can frequently produce large DNA alternation such as inversion, translocation and large deletion rather than point mutation. Mutation frequency was investigated using Arabidopsis visible phenotype loci and was 8 to 33 fold higher for 220 MeV carbon ions than for electrons. Mutation spectrum was investigated on the flower color of chrysanthemum cv to find that flower mutants induced by ion beams show complex and stripe types rather than single color. Polymerase chain reaction analysis was performed to investigate DNA alteration of mutations. In conclusion, the characteristics of ion beams for the mutation induction are 1) high frequency, 2) broad mutation spectrum, and 3) novel mutants. (S. Ohno)
Measurement of Self-Inductance.
Mak, S. Y.; Tao, P. K.
1988-01-01
Discusses four different methods for measuring self-inductance based on the definition of inductance, the alternative definition, phase difference and LC resonance. Provides circuit diagrams and typical oscilloscope traces. (YP)
Launcher Dynamic Data Acquisition
2012-07-31
external source such as one of the standard Inter Range Instrumentation Group ( IRIG ) time codes. However, it is usually worthwhile to dedicate one...channel on each system to recording properly formatted time code (usually IRIG B). This recorded channel with defined characteristics can be used...First Motion Timing Channel Identification T01 T02 P01 P02 A01 A02 A03 B01 B02 M01 M02 R01 R02 R03 BW01 IRIG -B Location/Orientation Outside
Ousley, Gilbert W., Sr.
1991-12-01
The utilization of the Delta 2 as the vehicle for launching Aristoteles into its near Sun synchronous orbit is addressed. Delta is NASA's most reliable launch vehicle and is well suited for placing the present Aristoteles spacecraft into a 400 m circular orbit. A summary of some of the Delta 2 flight parameters is presented. Diagrams of a typical Delta 2 two stage separation are included along with statistics on delta reliability and launch plans.
1975-03-01
Aluminum alloy 6063 -T6 was selected as the launch tube material to minimize fabrication problems and procurement, time. Tolerances are less...matrix as shown in Figure 10. After laying up the fiberglass reinforced epoxy laminate, the unit was vacuum-bag-cured at 350oF and T5 psi as shown
Mathematical Induction: A Pedagogical Discussion.
Ernest, Paul
1984-01-01
Discusses the nature of mathematical induction and what constitutes a correct proof by this method and common misconceptions of induction with recommendations for their remediation. The topic is also analyzed into behavioral skills and subjected to a conceptual analysis. Criteria for analyzing and evaluating textbook treatment of induction are…
Inductive Reasoning: A Training Approach
Klauer, Karl Josef; Phye, Gary D.
2008-01-01
Researchers have examined inductive reasoning to identify different cognitive processes when participants deal with inductive problems. This article presents a prescriptive theory of inductive reasoning that identifies cognitive processing using a procedural strategy for making comparisons. It is hypothesized that training in the use of the…
Hansen, Irving G.
Electromechanical actuators developed to date have commonly ultilized permanent magnet (PM) synchronous motors. More recently switched reluctance (SR) motors have been advocated due to their robust characteristics. Implications of work which utilized induction motors and advanced control techniques are discussed. When induction motors are operated from an energy source capable of controlling voltages and frequencies independently, drive characteristics are obtained which are superior to either PM or SR motors. By synthesizing the machine frequency from a high-frequency carrier (nominally 20 kHz), high efficiencies, low distortion, and rapid torque response are available. At this time multiple horsepower machine drives were demonstrated, and work is on-going to develop a 20 hp average, 40 hp peak class of aerospace actuators. This effort is based upon high-frequency power distribution and management techniques developed by NASA for Space Station Freedom.
Inductive Supervised Quantum Learning
Monràs, Alex; Sentís, Gael; Wittek, Peter
2017-05-01
In supervised learning, an inductive learning algorithm extracts general rules from observed training instances, then the rules are applied to test instances. We show that this splitting of training and application arises naturally, in the classical setting, from a simple independence requirement with a physical interpretation of being nonsignaling. Thus, two seemingly different definitions of inductive learning happen to coincide. This follows from the properties of classical information that break down in the quantum setup. We prove a quantum de Finetti theorem for quantum channels, which shows that in the quantum case, the equivalence holds in the asymptotic setting, that is, for large numbers of test instances. This reveals a natural analogy between classical learning protocols and their quantum counterparts, justifying a similar treatment, and allowing us to inquire about standard elements in computational learning theory, such as structural risk minimization and sample complexity.
Hansen, Irving G.
1990-01-01
Electromechanical actuators developed to date have commonly ultilized permanent magnet (PM) synchronous motors. More recently switched reluctance (SR) motors have been advocated due to their robust characteristics. Implications of work which utilized induction motors and advanced control techniques are discussed. When induction motors are operated from an energy source capable of controlling voltages and frequencies independently, drive characteristics are obtained which are superior to either PM or SR motors. By synthesizing the machine frequency from a high-frequency carrier (nominally 20 kHz), high efficiencies, low distortion, and rapid torque response are available. At this time multiple horsepower machine drives were demonstrated, and work is on-going to develop a 20 hp average, 40 hp peak class of aerospace actuators. This effort is based upon high-frequency power distribution and management techniques developed by NASA for Space Station Freedom.
Tuey, R. C.
1972-01-01
Computer solutions of linear programming problems are outlined. Information covers vector spaces, convex sets, and matrix algebra elements for solving simultaneous linear equations. Dual problems, reduced cost analysis, ranges, and error analysis are illustrated.
Undulative induction electron accelerator for the waste and natural water purification systems
Kulish, Victor V; Gubanov, I V
2001-01-01
The project analysis of Undulative Induction Accelerator (EH - accelerator) for the waste and natural water purification systems is accomplished. It is shown that the use of the four-channel design of induction block and the standard set of auxiliary equipment (developed earlier for the Linear Induction Accelerators - LINACs) allow to construct commercially promising purification systems. A quality analysis of the accelerator is done and the optimal parameters are chosen taking into account the specific sphere of its usage.
Classifying Linear Canonical Relations
Lorand, Jonathan
2015-01-01
In this Master's thesis, we consider the problem of classifying, up to conjugation by linear symplectomorphisms, linear canonical relations (lagrangian correspondences) from a finite-dimensional symplectic vector space to itself. We give an elementary introduction to the theory of linear canonical relations and present partial results toward the classification problem. This exposition should be accessible to undergraduate students with a basic familiarity with linear algebra.
Peterson, David; Stofleth, Jerome H.; Saul, Venner W.
2017-07-11
Linear shaped charges are described herein. In a general embodiment, the linear shaped charge has an explosive with an elongated arrowhead-shaped profile. The linear shaped charge also has and an elongated v-shaped liner that is inset into a recess of the explosive. Another linear shaped charge includes an explosive that is shaped as a star-shaped prism. Liners are inset into crevices of the explosive, where the explosive acts as a tamper.
T. (A)LVAREZ
2012-01-01
For a closed linear relation in a Banach space the concept of regularity is introduced and studied.It is shown that many of the results of Mbekhta and other authors for operators remain valid in the context of multivalued linear operators.We also extend the punctured neighbourhood theorem for operators to linear relations and as an application we obtain a characterization of semiFredholm linear relations which are regular.
Orbital effects due to gravitational induction
Bini, Donato; Giordano, Domenico
2015-01-01
We study the motion of test particles in the metric of a localized and slowly rotating astronomical source, within the framework of linear gravitoelectromagnetism, grounded on a Post-Minkowskian approximation of general relativity. Special attention is paid to gravitational inductive effects due to time-varying gravitomagnetic fields. We show that, within the limits of the approximation mentioned above, there are cumulative effects on the orbit of the particles either for planetary sources or for binary systems. They turn out to be negligible.
Finite element modelingof spherical induction actuator
Galary, Grzegorz
2005-01-01
The thesis deals with finite element method simulations of the two-degree of freedom spherical induction actuator performed using the 2D and 3D models. In some cases non-linear magnetization curves, rotor movement and existence of higher harmonics are taken into account. The evolution of the model leading to its simplification is presented. Several rotor structures are tested, namely the one-layer, two-layers and two-layers-with-teeth rotor. The study of some rotor parameters, i.e. t...
Lawson, C. L.; Krogh, F. T.; Gold, S. S.; Kincaid, D. R.; Sullivan, J.; Williams, E.; Hanson, R. J.; Haskell, K.; Dongarra, J.; Moler, C. B.
1982-01-01
The Basic Linear Algebra Subprograms (BLAS) library is a collection of 38 FORTRAN-callable routines for performing basic operations of numerical linear algebra. BLAS library is portable and efficient source of basic operations for designers of programs involving linear algebriac computations. BLAS library is supplied in portable FORTRAN and Assembler code versions for IBM 370, UNIVAC 1100 and CDC 6000 series computers.
Lawson, C. L.; Krogh, F. T.; Gold, S. S.; Kincaid, D. R.; Sullivan, J.; Williams, E.; Hanson, R. J.; Haskell, K.; Dongarra, J.; Moler, C. B.
1982-01-01
The Basic Linear Algebra Subprograms (BLAS) library is a collection of 38 FORTRAN-callable routines for performing basic operations of numerical linear algebra. BLAS library is portable and efficient source of basic operations for designers of programs involving linear algebriac computations. BLAS library is supplied in portable FORTRAN and Assembler code versions for IBM 370, UNIVAC 1100 and CDC 6000 series computers.
Inductive voltage adder (IVA) for submillimeter radius electron beam
Mazarakis, M.G.; Poukey, J.W.; Maenchen, J.E. [and others
1996-12-31
The authors have already demonstrated the utility of inductive voltage adder accelerators for production of small-size electron beams. In this approach, the inductive voltage adder drives a magnetically immersed foilless diode to produce high-energy (10--20 MeV), high-brightness pencil electron beams. This concept was first demonstrated with the successful experiments which converted the linear induction accelerator RADLAC II into an IVA fitted with a small 1-cm radius cathode magnetically immersed foilless diode (RADLAC II/SMILE). They present here first validations of extending this idea to mm-scale electron beams using the SABRE and HERMES-III inductive voltage adders as test beds. The SABRE experiments are already completed and have produced 30-kA, 9-MeV electron beams with envelope diameter of 1.5-mm FWHM. The HERMES-III experiments are currently underway.
A taxonomy of inductive problems.
Kemp, Charles; Jern, Alan
2014-02-01
Inductive inferences about objects, features, categories, and relations have been studied for many years, but there are few attempts to chart the range of inductive problems that humans are able to solve. We present a taxonomy of inductive problems that helps to clarify the relationships between familiar inductive problems such as generalization, categorization, and identification, and that introduces new inductive problems for psychological investigation. Our taxonomy is founded on the idea that semantic knowledge is organized into systems of objects, features, categories, and relations, and we attempt to characterize all of the inductive problems that can arise when these systems are partially observed. Recent studies have begun to address some of the new problems in our taxonomy, and future work should aim to develop unified theories of inductive reasoning that explain how people solve all of the problems in the taxonomy.
Lehmann, P. [Institut Franco-Allemand de Recherches de Saint-Louis, 68 (France)
2000-09-01
Electromagnetic rail launchers are already known to be capable of accelerating objects to speeds in excess of 2000 m/s with an overall efficiency of greater than 30%. Electromagnetic rail launchers are already finding numerous applications including the acceleration of small particles with a mass of around 1 g to speeds of over 12 km/s, the application of surface treatments, and the injection of solid deuterium pellets into the plasma in Tokamak fusion reactors. Future applications are expected to include the launching of small Earth orbiting satellites and as an alternative to traditional propellants in armaments. The current research at the St Louis Institute is concentrating on high-speed high-current sliding contacts and the electrical circuits needed to generate the powerful current pulses needed by this type of launcher. Researchers are developing multi-filament metal brushes capable of carrying a peak current of 700 kA when moving at 2000 m/s with no arcing at the interface between the rail and the projectile. The new launcher has an overall efficiency of around 30% and projectiles with a mass of between 350 g and 650 g have been accelerated to speeds of 2300 m/s. (authors)
Cooperstein, Bruce
2010-01-01
Vector SpacesFieldsThe Space FnVector Spaces over an Arbitrary Field Subspaces of Vector SpacesSpan and IndependenceBases and Finite Dimensional Vector SpacesBases and Infinite Dimensional Vector SpacesCoordinate VectorsLinear TransformationsIntroduction to Linear TransformationsThe Range and Kernel of a Linear TransformationThe Correspondence and Isomorphism TheoremsMatrix of a Linear TransformationThe Algebra of L(V, W) and Mmn(F)Invertible Transformations and MatricesPolynomialsThe Algebra of PolynomialsRoots of PolynomialsTheory of a Single Linear OperatorInvariant Subspaces of an Operator
新型舰载同心筒发射过程流场研究%Launching Process of the New Type Shipborne Concentric Canister Launcher
邵立武; 姜毅; 马艳丽; 王伟臣
2011-01-01
The internal-external canister space should be enough to exhaust jet flow when the concentric canister launcher is used. The common-frame launch is used for the shipborne weapon which would cause the small sizes of the internal canister and ballistic missile. To solve the problem, the external canister is designed to be rectangular. The internal-external canister space increases with the same common frame and the missile temperature decreases. The three-dimensional dynamic meshes were used to study the launching process of the concentric canister launcher. The zone moving and dynamic methods were used to update the meshes. The results showed that the location curve accord well with experiment. The missile surface temperature decreased greatly with the new type concentric canister launcher.%采用同心筒垂直发射装置,内外筒要保证足够的间隙尺寸用来排导燃气,目前舰载发射均采用通垂方式,势必使得内筒尺寸较小,从而导弹的直径也就较小,不利于发挥弹道导弹的优势.在此基础上提出将传统的外筒设计为一方形结构,在与相同尺寸的通垂架相连接的前提下,增加了内外筒之间燃气排导空间,降低发射过程中导弹表面的温度.计算中使用三维动网格更新方法对同心筒发射过程进行了计算研究,网格更新方法采用域动分层法.结果表明,导弹运动位移曲线与试验符合较好,新型同心筒方案使得整个发射过程中导弹表面的温度均明显降低.
Chavez, Ray; Harjes, Henry Charles III; Wallace, Zachariah; Elizondo, Juan E.
2007-10-01
The laser trigger switch (LTS) is a key component in ZR-type pulsed power systems. In ZR, the pulse rise time through the LTS is > 200 ns and additional stages of pulse compression are required to achieve the desired <100 ns rise time. The inductance of the LTS ({approx}500nH) in large part determines the energy transfer time through the switch and there is much to be gained in improving system performance and reducing system costs by reducing this inductance. The current path through the cascade section of the ZR LTS is at a diameter of {approx} 6-inches which is certainly not optimal from an inductance point of view. The LTS connects components of much greater diameter (typically 4-5 feet). In this LDRD the viability of switch concepts in which the diameter of cascade section is greatly increased have been investigated. The key technical question to be answered was, will the desired multi-channel behavior be maintained in a cascade section of larger diameter. This LDRD proceeded in 2 distinct phases. The original plan for the LDRD was to develop a promising switch concept and then design, build, and test a moderate scale switch which would demonstrate the key features of the concept. In phase I, a switch concept which meet all electrical design criteria and had a calculated inductance of 150 nH was developed. A 1.5 MV test switch was designed and fabrication was initiated. The LDRD was then redirected due to budgetary concerns. The fabrication of the switch was halted and the focus of the LDRD was shifted to small scale experiments designed to answer the key technical question concerning multi-channel behavior. In phase II, the Multi-channel switch test bed (MCST) was designed and constructed. The purpose of MCST was to provide a versatile, fast turn around facility for the study the multi-channel electrical breakdown behavior of a ZR type cascade switch gap in a parameter space near that of a ZR LTS. Parameter scans on source impedance, gap tilt, gap spacing and
Induction motor starting current
Arneaud, J.M.; Langman, R.A. [Tasmania Univ., Hobart, TAS (Australia)
1995-12-31
Large errors may occur if leakage path saturation is neglected when reduced-voltage test results are used to predict the direct-on-line starting current of induction motors. The results of applying three existing and two new methods for starting current prediction are compared with test data from 52 motors. A quantitative assessment is made of the probable reduction in error that would be achieved by increasing the number of available sets of reduced-voltage, locked rotor test results or by including slot design data. Guidelines are given for selecting an appropriate predictive method. (author). 4 tabs., 1 fig., 6 refs.
Non linear system become linear system
Petre Bucur
2007-01-01
Full Text Available The present paper refers to the theory and the practice of the systems regarding non-linear systems and their applications. We aimed the integration of these systems to elaborate their response as well as to highlight some outstanding features.
筒式发射器圆柱凸轮机构设计%Design of cylindrical cam mechanism in cylindrical launcher
郭三学
2011-01-01
针对火箭抛锚器的应用特点,采用筒式发射器的结构形式,设计了圆柱凸轮控制机构,通过等速推杆运动规律实现对火帽的准确击发,确定了凸轮轮廓曲线,圆柱凸轮机构经使用能安全可靠的击发火箭抛锚体.%The structure of the cylindrical launcher is adopted to design the cylindrical cam control mechanism according to the feature of the rocket anchor projectile. The precise percussion is realized by means of the constant velocity motion pattern The cam contour curve was confirmed. The practice indicates that the cylindrical cam mechanism can launch the rocket anchor projectile safely and reliably.
Pollard-Wright, Holly M; Wright, Mark T; Warren, Jeffrey M
2010-12-01
Prerelease reconditioning improves the chance of survival of rehabilitating raptors. Reconditioning may also help to rehabilitate waterfowl, including those that are threatened or endangered, especially if the birds are released during periods of migration. A flying harness, creance, remote-controlled launcher, and portable tower were used to create a means of reconditioning a rehabilitating 5-month-old female wild mallard duck (Anas platyrhynchos) that had been housed in a rehabilitation center for 7 weeks while recovering from an injury. Pre- and postflight serum lactate levels, body condition index scores, and controlled flight distances were used to assess the bird's degree of conditioning. Postflight serum lactate levels never returned to preflight levels and were not deemed a reliable indicator of physical fitness. However, the mallard showed an increase in endurance and strength as well as improved body condition index scores over the course of the reconditioning program.
Razhev, A M; Kargapol' tsev, E S [Institute of Laser Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation); Churkin, D S; Demchuk, S V [Novosibirsk State University, Novosibirsk (Russian Federation)
2016-03-31
We report the results of experimentally investigated dependences of temporal, spectral and spatial characteristics of an inductive HF-laser generation on the pump conditions. Gas mixtures H{sub 2} – F{sub 2}(NF{sub 3} or SF6{sub 6}) and He(Ne) – H{sub 2} – F{sub 2}(NF{sub 3} or SF{sub 6}) were used as active media. The FWHM pulse duration reached 0.42 μs. This value corresponded to a pulsed power of 45 kW. For the first time, the emission spectrum of an inductive HF laser was investigated, which consisted of seven groups of bands with centres around the wavelengths of 2732, 2736, 2739, 2835, 2837, 2893 and 2913 nm. The cross section profile of the laser beam was a ring with a diameter of about 20 mm and width of about 5 mm. Parameters of laser operation in the repetitively pulsed regime were sufficiently stable. The amplitude instability of light pulses was no greater than 5% – 6%. (lasers)
Phase-sensitive detection of both inductive and non-inductive ac voltages in ferromagnetic resonance
Weiler, Mathias; Shaw, Justin M.; Nembach, Hans T.; Schoen, Martin A.; Boone, Carl T.; Silva, Thomas J.
2014-03-01
Spin pumping causes significant damping in ultrathin ferromagnetic/normal metal (NM) multilayers via spin-current generation of both dc and ac character in the NM system. While the nonlinear dc component has been investigated in detail by utilization of the inverse spin Hall effect (iSHE) in NMs, much less is known about the linear ac component that is presumably much larger in the small-excitation limit. We measured generated ac voltages in a wide variety of Permalloy/NM multilayers via vector-network-analyzer ferromagnetic resonance. We employ a custom, impedance-matched, broadband microwave coupler that features a ferromagnetic thin film reference resonator to accurately compare ac voltage amplitudes and phases between varieties of multilayers. By use of the fact that inductive and ac iSHE signals are phase-shifted by π/2, we find that inductive signals are major contributors in all investigated samples. It is only by comparison of the phase and amplitude of the recorded ac voltages between multiple samples that we can extract the non-inductive contributions due to spin-currents. Voltages due to the ac iSHE in Permalloy(10nm)/platinum(5nm) bilayers are weaker than inductive signals, in agreement with calculations based upon recent theoretical predictions. M.W. acknowledges financial support by the German Academic Exchange service (DAAD).
Wiedemann, H.
1981-11-01
Since no linear colliders have been built yet it is difficult to know at what energy the linear cost scaling of linear colliders drops below the quadratic scaling of storage rings. There is, however, no doubt that a linear collider facility for a center of mass energy above say 500 GeV is significantly cheaper than an equivalent storage ring. In order to make the linear collider principle feasible at very high energies a number of problems have to be solved. There are two kinds of problems: one which is related to the feasibility of the principle and the other kind of problems is associated with minimizing the cost of constructing and operating such a facility. This lecture series describes the problems and possible solutions. Since the real test of a principle requires the construction of a prototype I will in the last chapter describe the SLC project at the Stanford Linear Accelerator Center.
Blyth, T S
2002-01-01
Basic Linear Algebra is a text for first year students leading from concrete examples to abstract theorems, via tutorial-type exercises. More exercises (of the kind a student may expect in examination papers) are grouped at the end of each section. The book covers the most important basics of any first course on linear algebra, explaining the algebra of matrices with applications to analytic geometry, systems of linear equations, difference equations and complex numbers. Linear equations are treated via Hermite normal forms which provides a successful and concrete explanation of the notion of linear independence. Another important highlight is the connection between linear mappings and matrices leading to the change of basis theorem which opens the door to the notion of similarity. This new and revised edition features additional exercises and coverage of Cramer's rule (omitted from the first edition). However, it is the new, extra chapter on computer assistance that will be of particular interest to readers:...
Linearity in Process Languages
Nygaard, Mikkel; Winskel, Glynn
2002-01-01
The meaning and mathematical consequences of linearity (managing without a presumed ability to copy) are studied for a path-based model of processes which is also a model of affine-linear logic. This connection yields an affine-linear language for processes, automatically respecting open-map bisi......The meaning and mathematical consequences of linearity (managing without a presumed ability to copy) are studied for a path-based model of processes which is also a model of affine-linear logic. This connection yields an affine-linear language for processes, automatically respecting open......-map bisimulation, in which a range of process operations can be expressed. An operational semantics is provided for the tensor fragment of the language. Different ways to make assemblies of processes lead to different choices of exponential, some of which respect bisimulation....
Matrices and linear transformations
Cullen, Charles G
1990-01-01
""Comprehensive . . . an excellent introduction to the subject."" - Electronic Engineer's Design Magazine.This introductory textbook, aimed at sophomore- and junior-level undergraduates in mathematics, engineering, and the physical sciences, offers a smooth, in-depth treatment of linear algebra and matrix theory. The major objects of study are matrices over an arbitrary field. Contents include Matrices and Linear Systems; Vector Spaces; Determinants; Linear Transformations; Similarity: Part I and Part II; Polynomials and Polynomial Matrices; Matrix Analysis; and Numerical Methods. The first
Shelah, Saharon
2011-01-01
We address the following question: Can we expand an NIP theory by adding a linear order such that the expansion is still NIP? Easily, if acl(A)=A for all A, then this is true. Otherwise, we give counterexamples. More precisely, there is a totally categorical theory for which every expansion by a linear order has IP. There is also an \\omega-stable NDOP theory for which every expansion by a linear order interprets bounded arithmetic.
Efficient Non Linear Loudspeakers
Petersen, Bo R.; Agerkvist, Finn T.
2006-01-01
Loudspeakers have traditionally been designed to be as linear as possible. However, as techniques for compensating non linearities are emerging, it becomes possible to use other design criteria. This paper present and examines a new idea for improving the efficiency of loudspeakers at high levels...... by changing the voice coil layout. This deliberate non-linear design has the benefit that a smaller amplifier can be used, which has the benefit of reducing system cost as well as reducing power consumption....
Carr, Joseph
1996-01-01
The linear IC market is large and growing, as is the demand for well trained technicians and engineers who understand how these devices work and how to apply them. Linear Integrated Circuits provides in-depth coverage of the devices and their operation, but not at the expense of practical applications in which linear devices figure prominently. This book is written for a wide readership from FE and first degree students, to hobbyists and professionals.Chapter 1 offers a general introduction that will provide students with the foundations of linear IC technology. From chapter 2 onwa
Charges for linearized gravity
Aksteiner, Steffen
2013-01-01
Maxwell test fields as well as solutions of linearized gravity on the Kerr exterior admit non-radiating modes, i.e. non-trivial time-independent solutions. These are closely related to conserved charges. In this paper we discuss the non-radiating modes for linearized gravity, which may be seen to correspond to the Poincare Lie-algebra. The 2-dimensional isometry group of Kerr corresponds to a 2-parameter family of gauge-invariant non-radiating modes representing infinitesimal perturbations of mass and azimuthal angular momentum. We calculate the linearized mass charge in terms of linearized Newman-Penrose scalars.
Chen, Qingwen; Narayanan, Kumaran
2015-01-01
Recombineering is a powerful genetic engineering technique based on homologous recombination that can be used to accurately modify DNA independent of its sequence or size. One novel application of recombineering is the assembly of linear BACs in E. coli that can replicate autonomously as linear plasmids. A circular BAC is inserted with a short telomeric sequence from phage N15, which is subsequently cut and rejoined by the phage protelomerase enzyme to generate a linear BAC with terminal hairpin telomeres. Telomere-capped linear BACs are protected against exonuclease attack both in vitro and in vivo in E. coli cells and can replicate stably. Here we describe step-by-step protocols to linearize any BAC clone by recombineering, including inserting and screening for presence of the N15 telomeric sequence, linearizing BACs in vivo in E. coli, extracting linear BACs, and verifying the presence of hairpin telomere structures. Linear BACs may be useful for functional expression of genomic loci in cells, maintenance of linear viral genomes in their natural conformation, and for constructing innovative artificial chromosome structures for applications in mammalian and plant cells.
Fault tolerant linear actuator
Tesar, Delbert
2004-09-14
In varying embodiments, the fault tolerant linear actuator of the present invention is a new and improved linear actuator with fault tolerance and positional control that may incorporate velocity summing, force summing, or a combination of the two. In one embodiment, the invention offers a velocity summing arrangement with a differential gear between two prime movers driving a cage, which then drives a linear spindle screw transmission. Other embodiments feature two prime movers driving separate linear spindle screw transmissions, one internal and one external, in a totally concentric and compact integrated module.
Faraway, Julian J
2014-01-01
A Hands-On Way to Learning Data AnalysisPart of the core of statistics, linear models are used to make predictions and explain the relationship between the response and the predictors. Understanding linear models is crucial to a broader competence in the practice of statistics. Linear Models with R, Second Edition explains how to use linear models in physical science, engineering, social science, and business applications. The book incorporates several improvements that reflect how the world of R has greatly expanded since the publication of the first edition.New to the Second EditionReorganiz
Lee, S Y; Park, B S; Yi, J H; Yi, W
1997-11-01
Gradient coil inductance has been remarkably reduced by the minimum-inductance design technique, which minimizes the magnetic energy stored by the gradient coil. The planar gradient coil designed by this technique, however, often has poor magnetic field linearity. Scaling the spatial frequencies of the current density function derived by this method, the magnetic field linearity of the planar gradient coil can be greatly improved with a small sacrifice of gradient coil inductance. A figure of merit of the planar gradient coil has been found to be improved by scaling the spatial frequencies.
Inductive limits and geometry of Banach spaces
Taskinen, Jari
1999-01-01
One of the main problems in the theory of inductive limits of Banach spaces is the projective description problem, finding a reasonable representation for the continuous seminorms. The problem is nontrivial even in the simplest cases. Recall that given, for example, an increasing sequence of Banach spaces (Yk)[infty infinity]k=1 with continuous embeddings Yk[hookrightarrow A: rt arrow-hooked]Yk+1 the inductive limit is the space Y=[cup B: union or logical sum]kYk endowed with the finest locally convex topology [tau] such that every embedding Yk[hookrightarrow A: rt arrow-hooked](Y, [tau]) becomes continuous. It is possible to give abstract definitions for families of continuous seminorms generating the topology [tau], but the connection with the norms of the step spaces Yk is not necessarily very close. For example, if the spaces Yk are Banach spaces of continuous functions endowed with weighted sup-norms, it is not clear if the continuous seminorms of the inductive limit are of the same type.We mention that inductive limits of spaces of continuous and holomorphic functions occur in many areas of analysis like linear partial differential operators, convolution equations [BD1], [E], complex and Fourier analysis and distribution theory. The projective description problem in these spaces has been thoroughly studied in [BMS1, BB1, BB2, BB3, BT, BM1, BM2], to mention some examples. We refer to the survey articles [BM1,BMS2, BB3]. The present work is also connected with the factorization problems which are treated in the book [Ju].
Vector control of induction machines
Robyns, Benoit
2012-01-01
After a brief introduction to the main law of physics and fundamental concepts inherent in electromechanical conversion, ""Vector Control of Induction Machines"" introduces the standard mathematical models for induction machines - whichever rotor technology is used - as well as several squirrel-cage induction machine vector-control strategies. The use of causal ordering graphs allows systematization of the design stage, as well as standardization of the structure of control devices. ""Vector Control of Induction Machines"" suggests a unique approach aimed at reducing parameter sensitivity for
Faltens, Andris
2011-01-07
The pulsers used in most of the induction linacs evolved from the very large body of work that was done in the U.S. and Great Britain during the development of the pulsed magnetron for radar. The radar modulators started at {approx}100 kW and reached >10 MW by 1945. A typical pulse length was 1 {mu}s at a repetition rate of 1,000 pps. A very comprehensive account of the modulator development is Pulse Generators by Lebacqz and Glasoe, one of the Radiation Laboratory Series. There are many permutations of possible modulators, two of the choices being tube type and line type. In earlier notes I wrote that technically the vacuum tube pulser met all of our induction linac needs, in the sense that a number of tubes, in series and parallel if required, could produce our pulses, regulate their voltage, be useable in feed-forward correctors, and provide a low source impedance. At a lower speed, an FET array is similar, and we have obtained and tested a large array capable of >10 MW switching. A modulator with an electronically controlled output only needs a capacitor for energy storage and in a switched mode can transfer the energy from the capacitor to the load at high efficiency. Driving a full size Astron induction core and a simulated resistive 'beam load' we achieved >50% efficiency. These electronically controlled output pulses can produce the pulses we desire but are not used because of their high cost. The second choice, the line type pulser, visually comprises a closing switch and a distributed or a lumped element transmission line. The typical switch cannot open or stop conducting after the desired pulse has been produced, and consequently all of the initially stored energy is dissipated. This approximately halves the efficiency, and the original cost estimating program LIACEP used this factor of two, even though our circuits are usually worse, and even though our inveterate optimists often omit it. The 'missing' energy is that which is
Cooling by Thermodynamic Induction
Patitsas, S. N.
2017-03-01
A method is described for cooling conductive channels to below ambient temperature. The thermodynamic induction principle dictates that the electrically biased channel will cool if the electrical conductance decreases with temperature. The extent of this cooling is calculated in detail for both cases of ballistic and conventional transport with specific calculations for carbon nanotubes and conventional metals, followed by discussions for semiconductors, graphene, and metal-insulator transition systems. A theorem is established for ballistic transport stating that net cooling is not possible. For conventional transport, net cooling is possible over a broad temperature range, with the range being size-dependent. A temperature clamping scheme for establishing a metastable nonequilibrium stationary state is detailed and followed with discussion of possible applications to on-chip thermoelectric cooling in integrated circuitry and quantum computer systems.
Cooling by Thermodynamic Induction
Patitsas, S. N.
2016-11-01
A method is described for cooling conductive channels to below ambient temperature. The thermodynamic induction principle dictates that the electrically biased channel will cool if the electrical conductance decreases with temperature. The extent of this cooling is calculated in detail for both cases of ballistic and conventional transport with specific calculations for carbon nanotubes and conventional metals, followed by discussions for semiconductors, graphene, and metal-insulator transition systems. A theorem is established for ballistic transport stating that net cooling is not possible. For conventional transport, net cooling is possible over a broad temperature range, with the range being size-dependent. A temperature clamping scheme for establishing a metastable nonequilibrium stationary state is detailed and followed with discussion of possible applications to on-chip thermoelectric cooling in integrated circuitry and quantum computer systems.
Kinetic inductance magnetometer.
Luomahaara, Juho; Vesterinen, Visa; Grönberg, Leif; Hassel, Juha
2014-09-10
Sensing ultra-low magnetic fields has various applications in the fields of science, medicine and industry. There is a growing need for a sensor that can be operated in ambient environments where magnetic shielding is limited or magnetic field manipulation is involved. To this end, here we demonstrate a new magnetometer with high sensitivity and wide dynamic range. The device is based on the current nonlinearity of superconducting material stemming from kinetic inductance. A further benefit of our approach is of extreme simplicity: the device is fabricated from a single layer of niobium nitride. Moreover, radio frequency multiplexing techniques can be applied, enabling the simultaneous readout of multiple sensors, for example, in biomagnetic measurements requiring data from large sensor arrays.
Ortega, Pedro A
2011-01-01
Discovering causal relationships is a hard task, often hindered by the need for intervention, and often requiring large amounts of data to resolve statistical uncertainty. However, humans quickly arrive at useful causal relationships. One possible reason is that humans use strong prior knowledge; and rather than encoding hard causal relationships, they encode beliefs over causal structures, allowing for sound generalization from the observations they obtain from directly acting in the world. In this work we propose a Bayesian approach to causal induction which allows modeling beliefs over multiple causal hypotheses and predicting the behavior of the world under causal interventions. We then illustrate how this method extracts causal information from data containing interventions and observations.
Youngquist, Robert C. (Inventor); Simmons, Stephen M. (Inventor)
2015-01-01
An inductive position sensor uses three parallel inductors, each of which has an axial core that is an independent magnetic structure. A first support couples first and second inductors and separate them by a fixed distance. A second support coupled to a third inductor disposed between the first and second inductors. The first support and second support are configured for relative movement as distance changes from the third inductor to each of the first and second inductors. An oscillating current is supplied to the first and second inductors. A device measures a phase component of a source voltage generating the oscillating current and a phase component of voltage induced in the third inductor when the oscillating current is supplied to the first and second inductors such that the phase component of the voltage induced overlaps the phase component of the source voltage.
Electromagnetic induction studies
Hermance, J. F.
1983-04-01
Recent developments in electromagnetic induction studies of the lithosphere and the asthenosphere are reviewed. Attention is given to geoelectrical studies of active tectonic areas in terms of the major zones of crustal extension, the basin and range province along western regions of North America, and the Rio Grande rift. Studies have also been performed of tectonic activity around Iceland, the Salton Trough and Cerro Prieto, and the subduction zones of the Cascade Mountains volcanic belt, where magnetotelluric and geomagnetic variation studies have been done. Geomagnetic variations experiments have been reported in the Central Appalachians, and submarine electromagnetic studies along the Juan de Fuca ridge. Controlled source electromagnetic and dc resistivity investigations have been carried out in Nevada, Hawaii, and in the Adirondacks Mountains. Laboratory examinations on the conductivity of representative materials over a broad range of temperature, pressure, and chemistry are described.
Inductive Electron Heating Revisited
Tuszewski, M.
1996-11-01
Inductively Coupled Plasmas (ICPs) have been studied for over a century. Recently, ICPs have been rediscovered by the multi-billion dollar semiconductor industry as an important class of high-density, low-pressure plasma sources suitable for the manufacture of next-generation integrated circuits. Present low-pressure ICP development is among the most active areas of plasma research. However, this development remains largely empirical, a prohibitively expensive approach for upcoming 300-mm diameter wafers. Hence, there is an urgent need for basic ICP plasma physics research, including experimental characterization and predictive numerical modeling. Inductive radio frequency (rf) power absorption is fundamental to the ICP electron heating and the resulting plasma transport but remains poorly understood. For example, recent experimental measurements and supporting fluid calculationsfootnote M. Tuszewski, Phys. Rev. Lett. 77 in press (1996) on a commercial deposition tool prototype show that the induced rf magnetic fields in the source can cause an order of magnitude reduction in plasma conductivity and in electron heating power density. In some cases, the rf fields penetrate through the entire volume of the ICP discharges while existing models that neglect the induced rf magnetic fields predict rf absorption in a thin skin layer near the plasma surface. The rf magnetic fields also cause more subtle changes in the plasma density and in the electron temperature spatial distributions. These data will be presented and the role of basic research in the applied world of semiconductor manufacturing will be discussed. ^*This research was conducted under the auspices of the U.S. DOE, supported by funds provided by the University of California for discretionary research by Los Alamos National Laboratory.
Yuce, C
2015-01-01
We predict the existence of linear discrete rogue waves. We discuss that Josephson effect is the underlying reason for the formation of such waves. We study linear rogue waves in continuous system and present an exact analytical rogue wave solution of the Schrodinger-like equation.
2014-01-01
© 2015 Elsevier B.V. Motivated by recent extensive studies on Wenger graphs, we introduce a new infinite class of bipartite graphs of a similar type, called linearized Wenger graphs. The spectrum, diameter and girth of these linearized Wenger graphs are determined.
A HIGH VELOCITY FEED UNIT DRIVEN BY LINEAR MOTOR
Zhang Bolin; Chen Yanji; Li Zhiying
2000-01-01
In order to realize high speed machining,the special requirements for feed transmission system of the CNC machine tool have to be satisfied.A high velocity feed unit driven by a induction linear motor is developed.The compositions of the high velocity CNC feed unit and main problems in the unit design are discussed.
Minimum Inductance Optimal Design for the Gradient Coil
无
2002-01-01
In MRI (Magnetic Resonance Imaging), a crucial role of gradient coils is to image organism, meanwhile the inductance of the coils determines the speed of imaging. So it is of great importance to optimize designs of the gradient coils. The target field approach is an effective method to design the gradient coils. Having applied this method and performing many numerical tests, we achieved the designs of the x-、y-、z- gradient coils , with the linearity of the fields generated by the coils in a sphere of radius 0.30 m less than 5%, in which the inductance and resistance of the coils also meet the requirements.
Numerical simulation of inclination vibration in magnetic induction micromachines
Chen, J-Y; Zhou, J-B; Zhang, W-M; Meng, G [State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China)], E-mail: jerrycc@sjtu.edu.cn
2008-02-15
This paper studies the inclination vibration of an axial-flux magnetic induction micromachine which is supported by hydrostatic thrust bearings. A mechanical model for the rotor and the corresponding fluid-film bearing is combined with an electromagnetic force model to study the linear and nonlinear rotordynamics of the system. Results obtained for the stability show that magnetic induction micromachine would encounter severe instability problem at high speed operations. The model developed here could serve as a useful reference for design optimization and operation scheme.
Numerical simulation of inclination vibration in magnetic induction micromachines
Chen, J.-Y.; Zhou, J.-B.; Zhang, W.-M.; Meng, G.
2008-02-01
This paper studies the inclination vibration of an axial-flux magnetic induction micromachine which is supported by hydrostatic thrust bearings. A mechanical model for the rotor and the corresponding fluid-film bearing is combined with an electromagnetic force model to study the linear and nonlinear rotordynamics of the system. Results obtained for the stability show that magnetic induction micromachine would encounter severe instability problem at high speed operations. The model developed here could serve as a useful reference for design optimization and operation scheme.
Efficient Non Linear Loudspeakers
Petersen, Bo R.; Agerkvist, Finn T.
2006-01-01
Loudspeakers have traditionally been designed to be as linear as possible. However, as techniques for compensating non linearities are emerging, it becomes possible to use other design criteria. This paper present and examines a new idea for improving the efficiency of loudspeakers at high levels...... by changing the voice coil layout. This deliberate non-linear design has the benefit that a smaller amplifier can be used, which has the benefit of reducing system cost as well as reducing power consumption.......Loudspeakers have traditionally been designed to be as linear as possible. However, as techniques for compensating non linearities are emerging, it becomes possible to use other design criteria. This paper present and examines a new idea for improving the efficiency of loudspeakers at high levels...
Axler, Sheldon
2015-01-01
This best-selling textbook for a second course in linear algebra is aimed at undergrad math majors and graduate students. The novel approach taken here banishes determinants to the end of the book. The text focuses on the central goal of linear algebra: understanding the structure of linear operators on finite-dimensional vector spaces. The author has taken unusual care to motivate concepts and to simplify proofs. A variety of interesting exercises in each chapter helps students understand and manipulate the objects of linear algebra. The third edition contains major improvements and revisions throughout the book. More than 300 new exercises have been added since the previous edition. Many new examples have been added to illustrate the key ideas of linear algebra. New topics covered in the book include product spaces, quotient spaces, and dual spaces. Beautiful new formatting creates pages with an unusually pleasant appearance in both print and electronic versions. No prerequisites are assumed other than the ...
A Student Teamwork Induction Protocol
Kamau, Caroline; Spong, Abigail
2015-01-01
Faulty group processes have harmful effects on performance but there is little research about intervention protocols to pre-empt them in higher education. This naturalistic experiment compared a control cohort with an inducted cohort. The inducted cohort attended a workshop, consultations, elected a leader and used tools (a group log and group…
Sampling Assumptions in Inductive Generalization
Navarro, Daniel J.; Dry, Matthew J.; Lee, Michael D.
2012-01-01
Inductive generalization, where people go beyond the data provided, is a basic cognitive capability, and it underpins theoretical accounts of learning, categorization, and decision making. To complete the inductive leap needed for generalization, people must make a key "sampling" assumption about how the available data were generated.…
From Inductive Reasoning to Proof
Yopp, David A.
2009-01-01
Mathematical proof is an expression of deductive reasoning (drawing conclusions from previous assertions). However, it is often inductive reasoning (conclusions drawn on the basis of examples) that helps learners form their deductive arguments, or proof. In addition, not all inductive arguments generate more formal arguments. This article draws a…
Westerhof, E.
2012-01-01
This lecture addresses the various ways of non-inductive current generation. In particular, the topics covered include the bootstrap current, RF current drive, neutral beam current drive, alternative methods, and possible synergies between different ways of non-inductive current generation.
Westerhof, E.
2010-01-01
This lecture addresses the various ways of non-inductive current generation. In particular, the topics covered include the bootstrap current, RF current drive, neutral beam current drive, alternative methods, and possible synergies between different ways of non-inductive current generation.
Misoprostol for induction of labor.
Stephenson, Megan L; Wing, Deborah A
2015-10-01
Labor-induction rates have increased considerably in the United States as well as around the world. With up to half of all induced labors requiring cervical ripening, prostaglandins have been utilized to increase induction success and achieve vaginal delivery. Misoprostol, a synthetic prostaglandin E1 analog has the ability to mimic the changes of spontaneous labor and has been used off label for over 30 years as a labor-induction agent. In the following article, cervical ripening and induction of labor with misoprostol will be discussed. The risks and benefits of misoprostol for ripening and induction and routes of administration will be reviewed, as well as future directions and new developments for its use.
Induction: The Early Years of Teaching.
Guyton, Edi; Davis, Douglas; Colarusso, Ron; Grainger, Barbara
2002-01-01
Addresses the need for induction programs for beginning teachers and discusses the theoretical and research support for them. Develops the notion of induction as a community responsibility and describes a university-school induction consortium, a university induction program, an induction program at a middle school, and the role of the principal…
Induction: The Early Years of Teaching.
Guyton, Edi; Davis, Douglas; Colarusso, Ron; Grainger, Barbara
2002-01-01
Addresses the need for induction programs for beginning teachers and discusses the theoretical and research support for them. Develops the notion of induction as a community responsibility and describes a university-school induction consortium, a university induction program, an induction program at a middle school, and the role of the principal…
Schneider, Hans
1989-01-01
Linear algebra is one of the central disciplines in mathematics. A student of pure mathematics must know linear algebra if he is to continue with modern algebra or functional analysis. Much of the mathematics now taught to engineers and physicists requires it.This well-known and highly regarded text makes the subject accessible to undergraduates with little mathematical experience. Written mainly for students in physics, engineering, economics, and other fields outside mathematics, the book gives the theory of matrices and applications to systems of linear equations, as well as many related t
Weisberg, Sanford
2013-01-01
Praise for the Third Edition ""...this is an excellent book which could easily be used as a course text...""-International Statistical Institute The Fourth Edition of Applied Linear Regression provides a thorough update of the basic theory and methodology of linear regression modeling. Demonstrating the practical applications of linear regression analysis techniques, the Fourth Edition uses interesting, real-world exercises and examples. Stressing central concepts such as model building, understanding parameters, assessing fit and reliability, and drawing conclusions, the new edition illus
Amir-Moez, A R; Sneddon, I N
1962-01-01
Elements of Linear Space is a detailed treatment of the elements of linear spaces, including real spaces with no more than three dimensions and complex n-dimensional spaces. The geometry of conic sections and quadric surfaces is considered, along with algebraic structures, especially vector spaces and transformations. Problems drawn from various branches of geometry are given.Comprised of 12 chapters, this volume begins with an introduction to real Euclidean space, followed by a discussion on linear transformations and matrices. The addition and multiplication of transformations and matrices a
Weisberg, Sanford
2005-01-01
Master linear regression techniques with a new edition of a classic text Reviews of the Second Edition: ""I found it enjoyable reading and so full of interesting material that even the well-informed reader will probably find something new . . . a necessity for all of those who do linear regression."" -Technometrics, February 1987 ""Overall, I feel that the book is a valuable addition to the now considerable list of texts on applied linear regression. It should be a strong contender as the leading text for a first serious course in regression analysis."" -American Scientist, May-June 1987
Abian, Alexander
1973-01-01
Linear Associative Algebras focuses on finite dimensional linear associative algebras and the Wedderburn structure theorems.The publication first elaborates on semigroups and groups, rings and fields, direct sum and tensor product of rings, and polynomial and matrix rings. The text then ponders on vector spaces, including finite dimensional vector spaces and matrix representation of vectors. The book takes a look at linear associative algebras, as well as the idempotent and nilpotent elements of an algebra, ideals of an algebra, total matrix algebras and the canonical forms of matrices, matrix
Unsupervised Linear Discriminant Analysis
无
2006-01-01
An algorithm for unsupervised linear discriminant analysis was presented. Optimal unsupervised discriminant vectors are obtained through maximizing covariance of all samples and minimizing covariance of local k-nearest neighbor samples. The experimental results show our algorithm is effective.
Isolated linear blaschkoid psoriasis.
Nasimi, M; Abedini, R; Azizpour, A; Nikoo, A
2016-10-01
Linear psoriasis (LPs) is considered a rare clinical presentation of psoriasis, which is characterized by linear erythematous and scaly lesions along the lines of Blaschko. We report the case of a 20-year-old man who presented with asymptomatic linear and S-shaped erythematous, scaly plaques on right side of his trunk. The plaques were arranged along the lines of Blaschko with a sharp demarcation at the midline. Histological examination of a skin biopsy confirmed the diagnosis of psoriasis. Topical calcipotriol and betamethasone dipropionate ointments were prescribed for 2 months. A good clinical improvement was achieved, with reduction in lesion thickness and scaling. In patients with linear erythematous and scaly plaques along the lines of Blaschko, the diagnosis of LPs should be kept in mind, especially in patients with asymptomatic lesions of late onset. © 2016 British Association of Dermatologists.
Linear systems theory revisited
Willigenburg, van L.G.; Koning, de W.L.
2008-01-01
This paper investigates and clarifies how different definitions of reachability, observability, controllability, reconstructability and minimality that appear in the control literature, may be equivalent or different, depending on the type of linear system. The differences are caused by (1) whether
Inductively generating Euler diagrams.
Stapleton, Gem; Rodgers, Peter; Howse, John; Zhang, Leishi
2011-01-01
Euler diagrams have a wide variety of uses, from information visualization to logical reasoning. In all of their application areas, the ability to automatically layout Euler diagrams brings considerable benefits. In this paper, we present a novel approach to Euler diagram generation. We develop certain graphs associated with Euler diagrams in order to allow curves to be added by finding cycles in these graphs. This permits us to build Euler diagrams inductively, adding one curve at a time. Our technique is adaptable, allowing the easy specification, and enforcement, of sets of well-formedness conditions; we present a series of results that identify properties of cycles that correspond to the well-formedness conditions. This improves upon other contributions toward the automated generation of Euler diagrams which implicitly assume some fixed set of well-formedness conditions must hold. In addition, unlike most of these other generation methods, our technique allows any abstract description to be drawn as an Euler diagram. To establish the utility of the approach, a prototype implementation has been developed.
Photorefractive writing and probing of anisotropic linear and non-linear lattices
Allio, Raphaël; Cantillano, Camilo; Morales-Inostroza, Luis; Lopez-Gonzalez, Dany; Etcheverry, Sebastián; Vicencio, Rodrigo A; Armijo, Julien
2014-01-01
We experimentally study the writing of one- and two-dimensional photorefractive lattices and the propagation of linear and nonlinear waves inside them. Using plane waves, we perform a time-resolved study of lattice writing and find good agreement with transient and steady-state photorefractive theory. In particular, the ratio of the drift to diffusion terms is proportional to the lattice period. We then analyze various wave propagation schemes. For focussed linear waves with broad transverse spectrum, we note that both the intensity distributions in real space ("discrete diffraction") and Fourier space ("Brillouin zone spectroscopy") reflect the Bragg planes and band structure. For non-linear waves, we observe modulational instability and time-domain discrete solitons formation. We discuss also the non-ideal effects inherent to the photo-induction technique : anisotropy, parasitic nonlinearity, diffusive term, and non-stationarity.
Linear and non-linear control of wind farms. Contribution to the grid stability
Fernandez, R.D. [Laboratorio de Electronica, Facultad de Ingenieria, Universidad Nacional de la Patagonia San Juan Bosco, Ciudad Universitaria, Km. 4, 9000, Comodoro Rivadavia (Argentina); Mantz, R.J. [Laboratorio de Electronica Industrial, Control e Instrumentacion (LEICI), Facultad de Ingenieria, Universidad Nacional de La Plata, CC 91, 1900, La Plata (Argentina); Comision de Investigaciones Cientificas de la Provincia de Buenos Aires, CICpBA, La Plata (Argentina); Battaiotto, P.E. [Laboratorio de Electronica Industrial, Control e Instrumentacion (LEICI), Facultad de Ingenieria, Universidad Nacional de La Plata, CC 91, 1900, La Plata (Argentina)
2010-06-15
This paper deals with linear and non-linear control of wind farms equipped with doubly-fed induction generators (DFIG). Both, active and reactive wind farm powers are employed in two independent control laws in order to increase the damping of the oscillation modes of a power system. In this way, it presented a general strategy where two correction terms are added, one by each independent control, to the normal operating condition of a wind farm. The proposed control laws are derived from the Lyapunov approach. Meanwhile for the reactive power a non-linear correction is presented, for the wind farm active power it is demonstrated that the classical proportional and inertial laws can be considered via the Lyapunov approach if wind farms are considered as real power plants, i.e. equivalent to conventional synchronous generation. Finally, some simulations are presented in order to support the theoretical considerations demonstrating the potential contributions of both control laws. (author)
Andrilli, Stephen
2010-01-01
Elementary Linear Algebra develops and explains in careful detail the computational techniques and fundamental theoretical results central to a first course in linear algebra. This highly acclaimed text focuses on developing the abstract thinking essential for further mathematical study. The authors give early, intensive attention to the skills necessary to make students comfortable with mathematical proofs. The text builds a gradual and smooth transition from computational results to general theory of abstract vector spaces. It also provides flexbile coverage of practical applications, expl
Callier, Frank M.; Desoer, Charles A.
1991-01-01
The aim of this book is to provide a systematic and rigorous access to the main topics of linear state-space system theory in both the continuous-time case and the discrete-time case; and the I/O description of linear systems. The main thrusts of the work are the analysis of system descriptions and derivations of their properties, LQ-optimal control, state feedback and state estimation, and MIMO unity-feedback systems.
1985-04-01
7.0 % % o the testing of an experimental linear motor driven expander using a standard production 1/4W split Stirling Common Module compressor. . - o...3 2.2 Expander Design CTI-CRYOGENICS has long recognized the potential of employing a linear drive motor to assist regenerator displacement and...assessment of the expander’s performance with lip seals and clearance seals for a regenerator comprised of nickel balls. Further comparison of a stainless
Høskuldsson, Agnar
1996-01-01
Determination of the proper dimension of a given linear model is one of the most important tasks in the applied modeling work. We consider here eight criteria that can be used to determine the dimension of the model, or equivalently, the number of components to use in the model. Four...... the basic problems in determining the dimension of linear models. Then each of the eight measures are treated. The results are illustrated by examples....
Mathematical models applied in inductive non-destructive testing
Wac-Wlodarczyk, A.; Goleman, R.; Czerwinski, D. [Technical University of Lublin, 20 618 Lublin, Nadbystrzycka St 38a (Poland); Gizewski, T. [Technical University of Lublin, 20 618 Lublin, Nadbystrzycka St 38a (Poland)], E-mail: t.gizewski@pollub.pl
2008-10-15
Non-destructive testing are the wide group of investigative methods of non-homogenous material. Methods of computer tomography, ultrasonic, magnetic and inductive methods still developed are widely applied in industry. In apparatus used for non-destructive tests, the analysis of signals is made on the basis of complex system answers. The answer is linearized due to the model of research system. In this paper, the authors will discuss the applications of the mathematical models applied in investigations of inductive magnetic materials. The statistical models and other gathered in similarity classes will be taken into consideration. Investigation of mathematical models allows to choose the correct method, which in consequence leads to precise representation of the inner structure of examined object. Inductive research of conductive media, especially those with ferromagnetic properties, are run with high frequency magnetic field (eddy-currents method), which considerably decrease penetration depth.
Antibody induction versus corticosteroid induction for liver transplant recipients
Penninga, Luit; Wettergren, André; Wilson, Colin H
2014-01-01
BACKGROUND: Liver transplantation is an established treatment option for end-stage liver failure. To date, no consensus has been reached on the use of immunosuppressive T-cell specific antibody induction compared with corticosteroid induction of immunosuppression after liver transplantation....... OBJECTIVES: To assess the benefits and harms of T-cell specific antibody induction versus corticosteroid induction for prevention of acute rejection in liver transplant recipients. SEARCH METHODS: We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register...... of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index Expanded, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) on 30 September 2013 together with reference checking, citation searching, contact with trial authors and pharmaceutical companies...
Statnikov, Vladimir; Sayadi, Taraneh; Meinke, Matthias; Schmid, Peter; Schröder, Wolfgang
2015-01-01
A sparsity promoting dynamic mode decomposition (DMD) combined with a classical data-based statistical analysis is applied to the turbulent wake of a generic axisymmetric configuration of an Ariane 5-like launcher at Ma∞ = 6.0 computed via a zonal Reynolds-averaged Navier-Stokes/large-eddy simulation (RANS/LES) method. The objective of this work is to gain a better understanding of the wake flow dynamics of the generic launcher by clarification and visualization of initially unknown pressure perturbation sources on its after-body in coherent flow patterns. The investigated wake topology is characterized by a subsonic cavity region around the cylindrical nozzle extension which is formed due to the displacement effect of the afterexpanding jet plume emanating from the rocket nozzle (Mae = 2.52, pe/p∞ = 100) and the shear layer shedding from the main body. The cavity region contains two toroidal counter-rotating large-scale vortices which extensively interact with the turbulent shear layer, jet plume, and rocket walls, leading to the shear layer instability process to be amplified. The induced velocity fluctuations in the wake and the ultimately resulting pressure perturbations on the after-body feature three global characteristic frequency ranges, depending on the streamwise position inside the cavity. The most dominant peaks are detected at SrD r3 = 0.85 ± 0.075 near the nozzle exit, while the lower frequency peaks, in the range of SrD r2 = 0.55 ± 0.05 and SrD r1 = 0.25 ± 0.05, are found to be dominant closer to the rocket's base. A sparse promoting DMD algorithm is applied to the time-resolved velocity field to clarify the origin of the detected peaks. This analysis extracts three low-frequency spatial modes at SrD = 0.27, 0.56, and 0.85. From the three-dimensional shape of the DMD modes and the reconstructed modulation of the mean flow in time, it is deduced that the detected most dominant peaks of SrD r3 ≈ 0.85 are caused by the radial flapping motion of
Optimal control of induction heating processes
Rapoport, Edgar
2006-01-01
This book introduces new approaches to solving optimal control problems in induction heating process applications. Optimal Control of Induction Heating Processes demonstrates how to apply and use new optimization techniques for different types of induction heating installations. Focusing on practical methods for solving real engineering optimization problems, the text features a variety of specific optimization examples for induction heater modes and designs, particularly those used in industrial applications. The book describes basic physical phenomena in induction heating and induction
Overview of Bearingless Induction Motors
Xiaodong Sun
2014-01-01
Full Text Available Bearingless induction motors combining functions of both torque generation and noncontact magnetic suspension together have attracted more and more attention in the past decades due to their definite advantages of compactness, simple structure, less maintenance, no wear particles, high rotational speed, and so forth. This paper overviews the key technologies of the bearingless induction motors, with emphasis on motor topologies, mathematical models, and control strategies. Particularly, in the control issues, the vector control, independent control, direct torque control, nonlinear decoupling control, sensorless control, and so forth are investigated. In addition, several possible development trends of the bearingless induction motors are also discussed.