A5102873336- Gyrotron and Vacuum Electronics Research
- Particle accelerators and beam dynamics
- Microwave Engineering and Waveguides
- Particle Accelerators and Free-Electron Lasers
- Magnetic confinement fusion research
- Thermochemical Biomass Conversion Processes
- Superconducting Materials and Applications
- Pulsed Power Technology Applications
- Physics and Engineering Research Articles
- Aviation Industry Analysis and Trends
- Biomimetic flight and propulsion mechanisms
- Orthopaedic implants and arthroplasty
- Air Traffic Management and Optimization
- Fusion materials and technologies
- Iron and Steelmaking Processes
- Orthopedic Infections and Treatments
- Micro and Nano Robotics
- Fluid Dynamics and Turbulent Flows
- Transportation Planning and Optimization
- Evolutionary Algorithms and Applications
- Plasma Diagnostics and Applications
- Total Knee Arthroplasty Outcomes
- Thermal and Kinetic Analysis
- Coal Combustion and Slurry Processing
- Advanced Electrical Measurement Techniques
Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)
2016-2017
Karlsruhe Institute of Technology
2010-2014
TU Wien
2011-2014
FZI Research Center for Information Technology
1995-2013
Bepress (United States)
2013
Institute of Technology of Cambodia
2012
ETH Zurich
2003-2011
Institute of Applied Physics
2011
FIZ Karlsruhe – Leibniz Institute for Information Infrastructure
2009-2010
Karlsruhe University of Education
1997-2008
SUMMARY The hydrodynamics of anguilliform swimming motions was investigated using three-dimensional simulations the fluid flow past a self-propelled body. motion body is not specified priori, but instead obtained through an evolutionary algorithm used to optimize efficiency and burst speed. results present support hypothesis that swimmers modify their kinematics according different objectives provide quantitative analysis forces experienced by characterized large amplitude tail undulations...
A 2-MW continuous-wave (CW) 170-GHz coaxial-cavity gyrotron for electron cyclotron heating and current drive in the International Thermonuclear Experimental Reactor (ITER) is under development within European Gyrotron Consortium (EGYC1), a cooperation between research institutions. To support of industrial prototype CW gyrotron, short-pulse tube (preprototype) used at KIT Karlsruhe (former FZK) experimental verification design critical components, like gun, beam tunnel, cavity, quasi-optical...
This paper investigates coaxial gyrotron cavities with longitudinal slots on the inner conductor as a means to reduce number of possible competing modes. In analytic theory corrugated surface is treated homogeneous impedance ("impedance corrugation") obtain simple formulas for characteristic equation eigenmodes, electromagnetic fields and wall losses. The developed model applies if sufficiently high (cutoff wavelength much larger than corruption period). in terms ratio C outer radius solved...
Megawatt gyrotrons are found to suffer from various parasitic oscillations, in particular, RF oscillations the beam tunnel prior desired interaction zone (the cavity). This paper describes experimental results a gyrotron experiment which was dedicated investigate and verify improved beam-tunnel structures. A system for spectral measurements new analysis method presented. The theoretical predictions on effect validate corresponding structure. In addition, other types of were observed explained.
A numerical method for the analysis of fields in highly oversized waveguides is proposed this paper. This allows simulation on waveguide walls with arbitrary surface deformations case that oversized, and wall are shallow smooth. Combined method, an algorithm has been developed synthesizing to provide a desired field distribution. As example, 309.6-mm-long launcher designed 170-GHz coaxial-cavity gyrotron transform TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML"...
Direct numerical simulation (DNS) of the channel flow with an anisotropic compliant surface is performed in order to investigate its drag reduction effect a fully developed turbulent flow. The computational domain set be 3δ×2δ×3δ, where δ half-width. passively driven by pressure and wall-shear stress fluctuations, velocity provides boundary condition for fluid field. An evolutionary optimization method (CMA-ES) used optimize parameters surface. identifies several sets that result friction...
The European Union is working toward providing 2-MW, coaxial-cavity, continuous-wave (cw) 170-GHz gyrotrons for ITER. Their design based on results from an experimental preprototype tube having a pulse length of several milliseconds, in operation at Forschungszentrum Karlsruhe (FZK) years now. first industrial prototype was designed cw but, phase, aimed 1 s the Gyrotron Test Facility Lausanne, Switzerland, as part phased testing/development program (1 s, 60 cw). this gyrotron are reported...
Co-gasification tests were carried out with wood pellets and lignite at ratios ranging from 0 to 100% in the dual fluidized bed pilot plant Vienna University of Technology. The operating parameters for all gasification co-gasification kept constant; input fuel power was chosen as 90 kWth while temperature held 850 °C. Olivine used material. In addition standard online measurements permanent gas components product gas, tar content also measured. NH3 H2S detected pure fuels. It turned that...
The design of a 1.5-MW, 140-GHz, TE-/sub 28,16/-coaxial cavity gyrotron is presented and results experimental operation are given. A with cylindrical outer wall radially tapered inner rod longitudinal corrugations was used. maximum output power 1.17 MW has been measured in the mode an efficiency 27.2%. Single-mode found over wide range operating parameters. values agree well multimode calculations. Frequency-step tuning performed between 115.6 164.2 GHz. In particular, 0.9 ben TE/sub 25,14/...
This work focuses on the cogasification of lignite and fresh polyethylene (PE) granulate at ratios ranging from 0 to 100% in dual fluidized bed pilot plant Vienna University Technology. The operating parameters for all gasification tests were kept constant. input fuel power was 90 kWth, while temperature 850 °C. Olivine used as material. In addition standard online measurements permanent components product gas, tar content also measured. Using feedstock improved quality terms reducing load...
The development of a coaxial-cavity gyrotron operating in TE/sub 31,17/ mode at 165 GHz is presented. selection the frequency and are based on limitations imposed by maximum held superconducting (sc) magnet Forschungzentrum Karlsruhe, Institut fur Technische Physik (FZK), use inverse-magnetron injection gun (IMIG) 140-GHz, 28,16/ coaxial possibility transforming cavity to whispering gallery (WGM) appropriate for dual-beam quasioptical (q.o.) output coupler two windows, which foreseen next...
A 1-MW, continuous wave, 170-GHz, TE32,9-mode gyrotron for use in International Thermonuclear Experimental Reactor (ITER) is under development within the European Gyrotron Consortium. quasi-optical mode converter employed to transform high-order cavity into a fundamental Gaussian wave beam. The contains launcher and mirror system. numerically optimized provide content of 98.43% at aperture. system consists three mirrors. first quasi-elliptical mirror, second third mirrors are beam-shaping...
Gyrotron oscillators are millimeter wave sources, capable of reaching megawatt power levels. Such high RF is required for electron cyclotron resonance heating and current drive systems future nuclear fusion facilities. With total system powers in the range up to about 100 MW, these installations call unit above 1 M W, reduce cost complexity complete system. In this paper, a mode selection process 4-MW 170-GHz coaxial-cavity gyrotron presented stable operating parameters elaborated. The...
The European Gyrotron Consortium (EGYC) is responsible for developing one set of 170 GHz mm-wave sources, in support Europe's contribution to ITER. original plan targeting a 2 MW coaxial gyrotron currently under discussion, view essential delays and damages. This paper reports on the latest results plans with regard two prototypes, industrial prototype at CRPP's CW test stand modular pre-prototype KIT. was delivered CRPP end September 2011 reached an output power efficiency 45 % good RF beam...