Search for dissertations about: "Exhaust Valve"

Showing result 1 - 5 of 33 swedish dissertations containing the words Exhaust Valve.

  2. 1. On Gas Dynamics of Exhaust Valves

    Author : Marcus Winroth; P. Henrik Alfredsson; Ramis Örlü; Knud Erik Meyer; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Exhaust valve; poppet valve; dynamic valve; engine modeling; discharge coefficient; Avgasventil; rörlig ventil; motorsimulering; utsläppskoefficient; Engineering Mechanics; Teknisk mekanik;

    Abstract : With increasing effects of global warming, efforts are made to make transportationin general more fuel efficient. When it comes to internal combustion engines,the most common way to improve fuel efficiency is through ‘downsizing’. Downsizingmeans that a smaller engine (with lower losses and less weight) performsthe task of a larger engine. READ MORE

  4. 2. Numerical Studies of Flow and AssociatedLosses in the Exhaust Port of a Diesel Engine

    Author : Yue Wang; Laszlo Fuchs; Mihai Mihaescu; Angelo Onorati; KTH; []
    Keywords : 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;

    Abstract : 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. READ MORE

  5. 3. Combustion Valve Wear : A Tribological Study of Combustion Valve Sealing Interfaces

    Author : Peter Forsberg; Staffan Jacobson; Rob Dwyer-Joyce; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Combustion valves; wear; tribofilm; test rig; combustion residue; Teknisk fysik med inriktning mot tribomaterial; Engineering Science with specialization in Tribo Materials;

    Abstract : The exhaust valve system of combustion engines experiences a very complex contact situation of frequent impact involving micro sliding, high and varying temperatures, complex exhaust gas chemistry and possible particulates, etc. In addition, the tribological situation in the exhaust valve system is expected to become even worse due to strict future emission regulations, which will require enhanced combustion and cleaner fuels. READ MORE

  6. 4. Simulations of compressible flows associatedwith internal combustion engines

    Author : Olle Bodin; Laszlo Fuchs; Mihai Mihaescu; Michael Leschziner; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LES; Gas exhange; exhaust port; exhaust manifold; POD; DMD; exhaust; LES; Gasväxling; avgasport; avgasgrenrör; POD; DMD;

    Abstract : Vehicles with internal combustion (IC) engines fueled by hydrocarbon compoundshave been used for more than 100 years for ground transportation.During these years and in particular the last decade, the environmental aspectsof IC engines have become a major political and research topic. READ MORE

  7. 5. Exhaust Heat Utilisation and Losses in Internal Combustion Engines with Focus on the Gas Exchange System

    Author : Habib Aghaali; Hans-Erik Ångström; Carlos Guardiola; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbocharger; heat transfer; heat loss; exhaust heat utilisation; waste heat recovery; turbocompound; divided exhaust period; internal combustion engine; gas exchange; pumping loss; variable valve timing; WHR; DEP; Turbo; värmeöverföring; värmeförluster; avgasvärme utnyttjande; förluster vid värmeåtervinning; turbocompound; delad avgasperiod; förbränningsmotor; gasväxling; pumpningsförlust; variabla ventiltider; WHR; DEP; Vehicle and Maritime Engineering; Farkostteknik; Energy Technology; Energiteknik;

    Abstract : Exhaust gas energy recovery should be considered in improving fuel economy of internal combustion engines. A large portion of fuel energy is wasted through the exhaust of internal combustion engines. Turbocharger and turbocompound can, however, recover part of this wasted heat. READ MORE