Diesel sprays – modeling and validation

Conference poster, 2011

Spray formation and combustion are highly complex processes, which have already been subjects of intense modeling efforts. If fuel is injected in gas a two-phase flow is generated, and several models have been developed to describe the gas and liquid phases, the models chosen are of course important for the results. Also, the way a model is implemented is important, especially regarding the treatment of the liquid core break-up process. It is not possible to estimate a single droplet size distribution for the whole spray, hence a spray model should generate a local droplet size distribution in the spray. However, the commonly applied models for primary and secondary break-up are not able to do this and often the spray model implementations are unstable and strongly grid size dependent. In the work presented here, the VSB2 spray model, developed by Volvo Technology Corporation, was implemented in OpenFOAM. The results obtained from VSB2 spray simulations are compared with data from experiments performed at Chalmers.