OpenFOAM-developments-around-fuel-injections-in-internal-combustion-engines

NIGRO NORBERTO

Wiesbaden

Congreso; 5th OpenFOAM User Conference 2017; 2017

ESI

The target of this work is the development of different numerical approximations tosimulate the fuel injection and its ultimately combustion inside a real opposed pistonengineinside the OpenFOAM suite. The key ingredients of this developments are first, theusage of an efficient dynamic mesh strategy with deformation and topologicalchanges using a combination of layering with AMI/ACMI for non-conformal couplingbetween different submeshes, exploiting the parallelism. In particular the AMI/ACMIimplementation rests on a definition of a pseudo supermesh that allows to reducesignificantly the cpu-time. Next the implementation of a particle tracking procedurewith different submodels for the atomization, spray formation, break-up andevaporation through an Eulerian (for the gas) and a Lagrangian (for fuel dropletparcels) all embedded in a parallel computation and finally the usage of a flameletcombustion model library to assess different proposals available in the literature.The phenomenological injection models are parameterized in terms of matchingvariables obtained from more detailed approaches. These last simulations are alsoincluded in this project using two different approaches, that may be available forgeneral usage very soon, inspired on pseudo DNS simulations of the primary andsecondary atomization processes employing either VOF-PLIC or a new methodology,called Particle Finite Volume Method. The former, very well known in the CFDcommunity, includes a geometric advection for the interface positioning coupledwith a height functions based curvature computation for the surface tension forces.The other methodology, an own development inspired on the Particle Finite ElementMethod (PFEM) that takes advantage of a combination of mesh and particle basedmethods with good properties in terms of boundedness, accuracy and efficiency, inparticular for multifluid flows. Advances in these two proposals are included also inthis presentation.This project has the following members: Horacion Aguerre, Santiago MarquezDamian, Cesar Pairetti, Juan Gimenez and Norberto Nigro