Sökning: "ignition front"

Visar resultat 1 - 5 av 17 avhandlingar innehållade orden ignition front.

1. 1. Numerical Studies of Methanol PPC Engines and Diesel Sprays

   Författare :Mateusz Pucilowski; Strömningsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Methanol; Partially Premixed Combustion PPC ; spray-wall interaction; piston geometry; multiple injections; ICE; ignition front; diffusion flame; combustion mode; RANS; LES; PPC; Diesel spray;

   Sammanfattning : The global environment suffers from utilizing fossil fuels to powering internal combustion engines (ICE), due to the massive amounts of released CO2. Besides the global impact, the local environments experience high concentrations of harmful pollutants such as NOx, CO, soot and particulate matter (PM). LÄS MER

3. 2. Zero and Multi-Dimensional Modeling of Internal Combustion Engines with respect to Ion Current and Soot Formation

   Författare :Abdelhadi Ahmedi; Institutioner vid LTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; engine knock; pollutant emissions; detailed chemical kinetics; thermal ionization.; ion current sensor; method of moments; ionization; soot formation oxidation; modeling; auto-ignition; Spark ignition engine; diesel engine;

   Sammanfattning : The work presented in this thesis can be divided into the three following fields of investigation: First of all the ionization model developed in this thesis is meant to simulate the thermal ionization process or the so-called second peak. Equilibrium assumptions have been adopted for the modeling of the thermal ionization, in which Saha’s equation was derived for singly ionized molecules. LÄS MER

4. 3. A numerical study of mixing phenomena and reaction front propagation in partially premixed combustion engines

   Författare :Christian Ibron; Strömningsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CFD simulation; förbränning; antändning;

   Sammanfattning : This work treats the modelling of PPC engine combustion through 3D computational fluid dynamics. In order to develop a cost-effective CFD model for the design and performance analysis of PPC engines it is important to first understand the multiple modes of combustion in PPC engines, e.g. LÄS MER

5. 4. Direct Numerical Simulations of Low Temperature Combustion in IC Engine Related Conditions

   Författare :Fan Zhang; Strömningsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : This thesis deals with direct numerical simulation (DNS) of low temperature combustion in internal combustion engine related conditions. In particular, HCCI (homogeneous charge compression ignition), SACI (spark assisted ho-mogeneous charge compression ignition) and PPC (partially premixed charge combustion) were investigated to gain deeper understanding on the details of the combustion process. LÄS MER

7. 5. Large Eddy Simulation of Turbulent Reactive Flows under HCCI Engine Conditions

   Författare :Tobias Joelsson; Strömningsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : Large Eddy Simulation (LES) modeling is developed to study homogeneous charge compression ignition (HCCI) combustion under different engine operation and mixture conditions, including real engine configurations and generic test cases. A previously developed HCCI model has been validated by comparing the simulation results with engine experiments. LÄS MER