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Visar resultat 1 - 5 av 8 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Multipactor in low pressure gas and in nonuniform rf field structures

    Författare :Richard Udiljak; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; detection methods; iris; low pressure gas; coax; nonuniform fields; Multipactor; microwave discharge; breakdown; discharge;

    Sammanfattning : Resonant electron multiplication in vacuum, multipactor, is analysed for several geometries where the RF electric field is nonuniform. In particular, it is shown that the multipactor behaviour in a coaxial line is both qualitatively and quantitatively different from that observed with the conventionally used simple parallel-plate model. LÄS MER

  3. 2. Numerical modelling of positive electrical discharges in long air gaps

    Författare :Oscar Diaz; Vernon Cooray; Raul Montano; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high voltage techniques; numerical modeling; electrical discharge in gases; streamer mechanism; leader channel; Engineering Science with specialization in Atmospheric Discharges; Teknisk fysik med inriktning mot atmosfäriska urladdningar;

    Sammanfattning : This dissertation deals with research on the numerical modelling of electrical discharges in laboratory long air gaps excited with positive switching impulses. It begins with the preliminary work of several scientists during the last decades, making a detailed analysis of different approaches for modelling all the stages in a full discharge. LÄS MER

  4. 3. Computer Modelling of Electrophysical Phenomena in High Voltage Insulation

    Författare :Yuriy Serdyuk; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dielectric properties; discharge plasma; composite material; computer model; numerical simulations; electrical discharge;

    Sammanfattning : Different kinds of dielectrics are used for high voltage insulation. In most of the cases, they are combined into complex insulating systems forming macro- and micro-scale composite structures. LÄS MER

  5. 4. Computational framework for studying charge transport in high-voltage gas-insulated systems

    Författare :Shailendra Singh; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; barrier discharge; low temperature plasma; drift diffusion equation; gaseous dielectrics; gas discharge; streamer propagation; high voltage;

    Sammanfattning : Electrical switchgear industry dealing with transmission and distribution of power is strongly affected by the changing dynamics of climate control. Their main contribution to the global warming is through SF6 gas, having a GWP of 23500 (times of CO2). SF6 plays an important role in providing electrical insulation for these high voltage systems. LÄS MER

  7. 5. Theoretical and Experimental Studies of the Formation of Ionized Gases in Spark Ignition Engines

    Författare :Raymond Reinmann; Förbränningsfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Thermal Ionization; Calorimetry; Interferometry; Spark Ignition Engine; Current and Voltage Measurements; Engine Control.; fluid dynamics; Gases; plasmas; Gaser; plasma; fluiddynamik; Breakdown; Arc; Glow; Flame Ionization; Chemi-Ionization; Spark; Townsend; Fysicumarkivet A:1998:Reinmann;

    Sammanfattning : The processes that govern the formation, existence and consumption of ions in gases have been studied both experimentally and theoretically. The aim of the work is targeted at increasing the understanding of these phenomena in the working gases inside an engine. LÄS MER