Development of a Validated CFD Process for the Analysis of Inlet Manifold Flows with EGR

Exhaust Gas Recirculation (EGR) is one of several technologies that are being investigated to deliver future legislative emissions targets for diesel engines. Its application requires a detailed understanding of the thermo-fluidic processes within the engine's air system. A validated Computational Fluid Dynamics (CFD) process is one way of providing this understanding.

This paper describes a CFD process to analyse unsteady manifold flows and mixing fields in the presence of realistic levels of EGR. The validation methodology was drawn from the American Institute of Aeronautics and Astronautics (AIAA) and divides the problem into smaller elemental problems. Detailed knowledge about these elemental problems is easily attainable, reducing the requirement for a large number of complex validation runs.

The final validated process was compared to flow visualization and particle image velocimetry (PIV) data collected from a motored engine. This comparison confirmed the CFD validation technique was appropriate for the analysis of unsteady manifold flows with EGR.