Sökning: "Premixed Charge"

Visar resultat 1 - 5 av 38 avhandlingar innehållade orden Premixed Charge.

1. 1. On the Impact of Piston Motion and In-Cylinder Charge Composition on Energy Release, Auto Ignition and Emission Formation in Premixed Charge Internal Combustion Engines

   Författare :Ola Stenlåås; Förbränningsmotorer; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bränslen; sprängämnen; Carbochemistry; petrochemistry; fuels and explosives technology; Petrokemi; Internal Combustion Engine; Emission; SI; Spark Ignition; HCCI; Homogeneous Charge Compression Ignition; zone model; Chemical Kinetic; Engine simulation; Reformed Methanol; Hydrogen; Knock; Auto Ignition; NO; Piston Motion; Nitric Oxide; Premixed Charge;

   Sammanfattning : The results presented in this thesis can be divided into four areas of investigation: Investigation of the effect of new volume-crank angle relations on engine emissions, power and efficiency; investigation of nitrogen oxides effect on auto ignition and knock in SI engines; investigation of premixed SI and HCCI engine operation with the alternative fuels hydrogen and reformed methanol gas (RMG); software development of a detailed chemical kinetics zonal engine model. Model development of the in-house two-zone chemical kinetic code focused on expansion of the Jacobian matrix to allow simulations of variable in-cylinder charge. LÄS MER

3. 2. System Simulation of Partially Premixed Combustion in Heavy-Duty Engines : Gas Exchange, Fuels and In-cylinder Analysis

   Författare :Erik Svensson; Förbränningsmotorer; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Partially Premixed Combustion PPC ; Compression ignition; Direct injection; Methanol; Engine optimization; Stochastic reactor model; T-phi diagrams; Partially premixed combustion; Compression Ignition; Direct Injection; Methanol; Engine Optimization; Stochastic reactor model; Gas exchange; T-phi diagrams;

   Sammanfattning : The concept of partially premixed combustion (PPC), applied to conventional diesel engines, has shown to yield high gross efficiencies and low emissions of oxides of nitrogen and soot. PPC emerged from the knowledge gained from homogeneous charge compression ignition (HCCI) research. LÄS MER

4. 3. Extension of OpenFOAM Library for RANS Simulation of Premixed Turbulent Combustion

   Författare :Ehsan Yasari; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TFC model. FSC model; Premixed turbulent combustion; Simulation; Modeling; OpenFOAM; Turbulent flow;

   Sammanfattning : Unsteady multi-dimensional numerical simulation of turbulent flames is a well recognized tool for research and development of future internal combustion engines capable for satisfying stringent requirements for ultra-low emission and highly efficient energy conversion. To attain success, such simulations need, in particular, well elaborated Computational Fluid Dynamics (CFD) software, as well as advanced predictive models of turbulent burning. LÄS MER

5. 4. Development and application of laser diagnostics - from laboratory devices towards practical combustion engines

   Författare :Zhenkan Wang; Förbränningsfysik; []
   Nyckelord :Combustion diagnostics; Laser induced fluorescence LIF ; Ultra-high-speed; Burst-mode laser; Ballistic imaging; Particle imaging velocimetry; Laser Doppler anemometry; Turbulent premixed combustion; Plasma; Internal combustion engine; Partially premixed combustion PPC ; Auto-ignition; OH radical; CH2O formaldehyde ; Fysicumarkivet A:2018:Wang;

   Sammanfattning : For many decades, research work on combustion has been focused on improving combustion efficiency and reducing harmful emissions. Laser diagnostics is one of the best ways to investigate the combustion process and emission formation as it is non-intrusive and it has high spatiotemporal resolution. LÄS MER

7. 5. Challenges and Advantages of Stratified Combustion in Gasoline Direct-Injected Engines

   Författare :Anders Johansson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Particulate Mass; SGDI; Particulate Number; Direct-Injected; GDI; Particulate Sampling; Spray-Guided; Particulates; Stratified Charge; Gasoline; DI;

   Sammanfattning : The modern world is based on an extensive transport network in which passenger vehicles play a major role. Although passenger vehicles have improved significantly in recent decades, they still contribute to the pollution of our environment and global warming. Consequently, new ways of reducing their emissions are needed. LÄS MER