Sökning: "Losses"

Visar resultat 6 - 10 av 1392 avhandlingar innehållade ordet Losses.

  1. 6. Numerical Studies of Flow and AssociatedLosses in the Exhaust Port of a Diesel Engine

    Författare :Yue Wang; Laszlo Fuchs; Mihai Mihaescu; Angelo Onorati; KTH; []
    Nyckelord :Internal Combustion Engine; Exhaust flow; Exhaust Valve; Exhaust Port; Large Eddy Simulation; Valve and Piston Motion; Total Pressure Losses; Energy Losses; Discharge coefficient; Flow Losses; Flow structures; Air Flow Bench; Engine-like Conditions; SRA - Energy; SRA - Energi;

    Sammanfattning : In the last decades, the focus of internal combustion engine development has moved towards more efficient and less pollutant engines. In a Diesel engine, approximately 30-40% of the energy provided by combustion is lost through the exhaust gases. The exhaust gases are hot and therefore rich of energy. LÄS MER

  3. 7. Electromagnetic Modelling of Power Transformers for Study and Mitigation of Effects of GICs

    Författare :Seyedali Mousavi; Göran Engdahl; Ebrahim Rahimpour; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; transformer; hysteresis; DC magnetization; GMD; GICs; FEM; reluctance network method; low frequency transients; core losses; winding losses; eddy current losses; transformator; hysteresis; DC; likströmsmagnetisering; GMD; GIC; FEM; reluktansnätverksmodell; lågfrekventa transienter; kärnförluster; lindningsförluster; virvelströmsförluster; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Geomagnetic disturbances that result from solar activities can affect technological systems such as power networks. They may cause DC currents in power networks and saturation of the core in power transformers that leads to destruction in the transformer performance. LÄS MER

  4. 8. Iron Losses in Electrical Machines - Influence of Material Properties, Manufacturing Processes, and Inverter Operation

    Författare :Andreas Krings; Juliette Soulard; Oskar Wallmark; Annette Mütze; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; AC machines; cobalt-iron; eddy current losses; electrical steel sheets; inverter-fed machines; iron alloys; iron loss measurements; machine design; magnetic hysteresis; magnetic losses; magnetic materials; nickel-iron; permanent magnet machines; silicon-iron; soft magnetic composites; slot-less machines; soft magnetic materials; thermal effects.; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : As the major electricity consumer, electrical machines play a key role for global energy savings. Machine manufacturers put considerable efforts into the development of more efficient electrical machines for loss reduction and higher power density achievements. LÄS MER

  5. 9. Experimental Study on Truck Related Power Losses: The Churning Losses in a Transmission Model and Active Flow Control at an A-pillar of Generic Truck Cabin Model

    Författare :Erwin Adi Hartono; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hot wire anemometry; Machine learning; Computational Fluid Dynamics; A-Pillar; Transmission; Flow separation; Churning losses; CFD; Gearbox; Torque measurement; Particle Image Velocimetry; Smoothed Particle Hydrodynamics.; Active Flow Control; SPH; Curve fit; Synthetic Jets; Load independent power losses; Aeration; Flow visu- alization;

    Sammanfattning : The fight with global warming constantly forces vehicle manufacturers to innovate, in order to be able to reduce the CO2 emissions of their product. This means that marginal efficiency gains in every component are considered beneficial for total reduction of CO2 emissions. LÄS MER

  7. 10. On the Design of Electric Traction Machines : Design and Analysis of an Interior Permanent Magnet Synchronous Machine for Heavy Commercial Vehicles

    Författare :Rasmus Andersson; Industriell elektroteknik och automation; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Design of electrical machines; IPMSM; Electric propulsion; Thermal model; Skewing; Torque ripple analysis; Mechanical losses; Iron losses; Loss analysis; Heavy commercial vehicles;

    Sammanfattning : Recent years have proven the benefits of electrifying the road bound vehicle fleet. With new components entering, the general understanding as well as the components as such needs to be improved. LÄS MER