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Projects: Projects for Investigator
Reference Number EP/E022219/1
Title Large Eddy Simulation of Diesel Engine Combustion with Detailed Chemistry
Status Completed
Energy Categories Energy Efficiency(Transport) 40%;
Not Energy Related 50%;
Fossil Fuels: Oil Gas and Coal(Oil and Gas, Oil and gas combustion) 10%;
Research Types Basic and strategic applied research 100%
Science and Technology Fields ENGINEERING AND TECHNOLOGY (Mechanical, Aeronautical and Manufacturing Engineering) 100%
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Dr A Marquis
No email address given
Department of Mechanical Engineering
Imperial College London
Award Type Standard
Funding Source EPSRC
Start Date 01 May 2007
End Date 31 October 2010
Duration 42 months
Total Grant Value £352,073
Industrial Sectors Transport Systems and Vehicles
Region London
Programme Energy : Engineering
 
Investigators Principal Investigator Dr A Marquis , Department of Mechanical Engineering, Imperial College London (99.998%)
  Other Investigator Dr AD Gosman , Department of Mechanical Engineering, Imperial College London (0.001%)
Dr A Kronenburg , University of Stuttgart, Germany (0.001%)
  Industrial Collaborator Project Contact , Ford Research Centre, USA (0.000%)
Project Contact , Sandia National Laboratories, USA (0.000%)
Web Site
Objectives
Abstract In recent times, immense efforts have been made in engine research to develop new concepts, from common-rail Diesel and GDI to HCCI (now primarily seen as an operating mode of the aforementioned), in order to meet increasingly-stringent demands for fuel consumption and emissions reductions. There is an urgent need for accurate simulation tools, ideally applicable to all engine types and operating modes, to assist engine designers to meet these targets. The modelling of turbulent reactive flowshas always been a trade-off between capturing the complexity of the flow and the complexity of the chemical kinetics (with due regard for turbulent-chemistry interactions), due to the limitations in computer resources. The former is particularly demanding in ICE modelling and has tended in the past to receive most of the attention, but over the past decade increasing effort has gone into the combustion modelling, due to the availability of high-power and low-cost computers.IC engine developmentleads towards novel diesel combustion concepts that break the traditional NOx vs. PM trade-off of classic diffusion controlled combustion require. Pollutant formation in Diesel engines is mainly mixing controlled and a better understanding of the complex turbulence-chemistry interactions that strongly influence the formation and destruction of pollutants is required. The proposed research will extend the existing CFD methodology for engine simulation to accurately account for (i) mixing offueland oxidizer, especially due to large-scale motion, (ii) turbulence-chemistry interactions and (iii) cycle-to-cycle variations that cannot be predicted by current state-of-the-art three-dimensional Reynolds-averaged simulations (RAS). It is widely accepted that large-eddy simulation (LES) holds the largest potential of all present fluid dynamics models to accurately capture large-scale mixing and cyclic effects of in-cylinder motion, however, LES needs be combined with advanced combustionmodelsfor the correct treatment of the turbulence-chemistry interactions. Very recent studies have established the potential of the conditional moment closure (CMC) approach as a suitable combustion model for IC engines and as a suitable combustion sub-model in the LES context. This potential will now be exploited and the integration of CMC into LES for engine computations is at the core of this project. The research will primarily focus on the closure of the turbulent reaction rate term, associatedturbulence-chemistry interactions and improvements to pollutant predictions. The effects of LES modelling on droplet motion, large-scale fuel-oxidizer mixing and the predictability of cyclic variations will be assessed. The LES-CMC approach will be validated by comparison with measurements from engine-like experiments of increasing complexity and trends for the dependence of NOx and soot emissions on engine operating conditions will be investigated
Publications (none)
Final Report (none)
Added to Database 01/01/07