Sökning: "complex permeability"

Visar resultat 6 - 10 av 104 avhandlingar innehållade orden complex permeability.

  1. 6. A High Frequency Transformer Winding Model for FRA Applications

    Författare :Hanif Tavakoli; Göran Engdahl; Jonas Ekman; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; complex permeability; frequency response analysis; time domain reflectometry; high frequency modeling; transformer diagnosis; Electrical engineering; Elektroteknik;

    Sammanfattning : Frequency response analysis (FRA) is a method which is used to detect mechanical faults in transformers. The FRA response of a transformer is determined by its geometry and material properties, and it can be considered as the transformer’s fingerprint. LÄS MER

  3. 7. Effect of Dielectric and Magnetic Material Characteristics on Frequency Response of Power Transformers

    Författare :Nilanga Abeywickrama; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; frequency response analysis; dielectric insulation; Complex permeability; core magnetization; finite element method; transformer diagnosis.; high frequency modelling; magnetic viscosity; silicon steel;

    Sammanfattning : Frequency response analysis (FRA) technique has become increasingly popular for the assessment of mechanicalintegrity in power transformers. This method is based on the fact that the shape of the frequency response at higher frequencies is uniquely determined by the geometrical construction of the transformer. LÄS MER

  4. 8. Electromagnetic Modeling with Complex Dielectrics : A Partial Element Equivalent Circuit Approach

    Författare :Andreas Hartman; Jonas Ekman; Jerker Delsing; Frank Gronwald; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Industrial Electronics; Industriell elektronik;

    Sammanfattning : Wireless communication systems have become an integral part of many complex systems in diverse areas of society, for the exchange of data in business and industrial settings. With the advent of Internet of Things (IoT) and wireless sensor network architectures, the tighter demands on interoperability between different devices are putting heavy requirements their ability to exchange data wirelessly among them reliably. LÄS MER

  5. 9. CO2 storage in deep saline aquifers : Models for geological heterogeneity and large domains

    Författare :Liang Tian; Auli Niemi; Fritjof Fagerlund; Simon Mathias; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; CO2; Carbon Capture Storage; Storage Capacity; Injectivity; Monte Carlo; Gaussian; Permeability; Upscaling; 二氧化碳; 地質封存; 高斯仿真; 滲透係數; 非均質性; 升尺度; 存儲效能; 場地模擬; 不確定性; 壓力累積;

    Sammanfattning : This work presents model development and model analyses of CO2 storage in deep saline aquifers. The goal has been two-fold, firstly to develop models and address the system behaviour under geological heterogeneity, second to tackle the issues related to problem scale as modelling of the CO2 storage systems can become prohibitively complex when large systems are considered. LÄS MER

  7. 10. On Diffusion Transport Properties in Fuel Cell Gas Diffusion Layers Using the Lattice Boltzmann Method

    Författare :Mayken Espinoza Andaluz; Värmeöverföring; []
    Nyckelord :PEFC; lattice Boltzmann method; gas diffusion layers; porosity; Gas-phase tortuosity; permeability; inertial coefficient; diffusibility; pore-scale modeling;

    Sammanfattning : The polymer electrolyte fuel cell (PEFC) is considered as one of the most promising devices for providing efficient, clean and noiseless conversion of chemical energy to electrical energy. This device can provide electrical and thermal energy for transport, mobile and stationary applications ranging in a wide range of power requirements. LÄS MER