- 14 March 2007 -

Software to aid design of diesel particulate filters

Researchers could save time testing diesel particulate filters with a new software simulation, the FilterDict 3-D. Up till now, researchers and developers have had to build filter prototypes to test which filters are most efficient at extracting the noxious particles and how geometrical details of the filter materials affect the filter properties, say its makers from the Fraunhofer Institute for Industrial Mathematics ITWM in Kaiserslautern, Germany.

The FilterDict 3-D could in future significantly reduce the number of prototypes required, cutting the time and cost of development – and offer some new features, says its makers.

“Our FilterDict 3-D simulation program for the first time gives us full insight into the filter processes – information which often cannot be obtained from practical tests,” claims simulation developer Dr. Stefan Rief of the Institute. “This allows us to simulate how fast and how far particles penetrate into the filter, for example – using any kind of filter material.”

As its input variables, FilterDict uses the filter material model from the existing GeoDict micro-structure generator, various physical parameters, and the particle size distribution. Depending on the type of filter material, other parameters – such as the direction of the fibres in fibrous filters – may also be taken into account. On the basis of this information, the program calculates the path of the soot particles through the filter media – for each one of the billions of particles. “The simulation helps us to find out how much soot is deposited in which part of the filter. We optimize the design of the filter to achieve long regeneration intervals, low fuel consumption and a high engine rating,” Rief says.

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