Search for dissertations about: "variable valve timing"

Showing result 1 - 5 of 11 swedish dissertations containing the words variable valve timing.

  2. 1. Study of a Pneumatic Hybrid aided by a FPGA Controlled Free Valve Technology System

    Author : Sasa Trajkovic; Förbränningsmotorer; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Compressor; Air-motor; Pneuamtc; Pneumatic-hybrid; VVT; Valve; regenerative; Hybrid; Air;

    Abstract : Urban traffic involves frequent acceleration and deceleration. During deceleration, the energy previously used to accelerate the vehicle is mainly wasted on heat generated by the friction brakes. If this energy that is wasted in traditional IC engines could be saved, the fuel economy would improve. READ MORE

  4. 2. Control of HCCI by aid of Variable Valve Timings with Specialization in Usage of a Non-Linear Quasi-Static Compensation

    Author : Fredrik Agrell; Hans-Erik Ångström; Wai K. Cheng; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HCCI; Homogeneous; Charge Compression Ignition; Engine Control; Variable Valve Timings; Other technology; Övriga teknikvetenskaper;

    Abstract : This doctoral thesis is about controlling the combustion timing of the combustion concept Homogeneous Charge Compression Ignition, HCCI, by means of variable valve timings. The HCCI research usually is regarded to have started in Japan during the later part of the 1970´s. The world of HCCI has since grown and HCCI is of today researched worldwide. READ MORE

  5. 3. HCCI Combustion by Retaining Residuals. Development and Analyses of a Method to Reduce Fuel Consumption for Passenger Car Gasoline Engines

    Author : Lucien Koopmans; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; gasoline; variable valve timing; homogeneous charge compression ignition HCCI ; internal combustion engines; fuel-consumption; engine emissions; controlled auto-ignition CAI ;

    Abstract : The demand for more powerful engines on one hand, and greater fuel-efficiency on the other, requires a revolution in engine combustion technology. Homogeneous charge compression ignition (HCCI) can be a fuel-saving, low emissions approach that seems to be very suitable for large displacement passenger car engines. READ MORE

  6. 4. 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

  7. 5. Variable Valve Actuation in a Spark Ignition Engine - A Flow Field and Heat Release Study

    Author : Fredrik Söderberg; Förbränningsmotorer; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; framdrivningssystem; Gases; plasma; fluid dynamics; plasmas; Gaser; fluiddynamik; vakuumteknik; vibrationer; akustik; Motors and propulsion systems; Motorer; hydraulik; Maskinteknik; vibration and acoustic engineering; Laser Doppler Velocimetry Particle Image Velocimetry PIV LDV Wavelet Computational Fluid Dynamics CFD Variable Valve Actuation Timing Turbulence Combustion Engine Spark Ignition Miller; hydraulics; vacuum technology; Mechanical engineering;

    Abstract : The objective of this thesis was to find ways of improving part-load efficiency for a spark ignition engine by studying the effects of variable-valve actuation on fluid flow and combustion. The in-cylinder flow was measured with laser doppler velocimetry, LDV, and particle image velocimetry, PIV. READ MORE