Simulation and experimental measurement of dynamic behavior of solid foam filter for diesel exhaust gas

A new diesel particulate filter (DPF) based on solid β-SiC foam is presented in this work. This solid foam filter becomes a promising alternative to the common wall flow filter, as it is effective in filtering ultra fine soot particles and provides a larger specific surface area for catalytic coating. This new DPF is validated with a series of experiments, which are realized on real bench test. A simplified descriptive model based on the new analogy between solid foams and fiber filter is developed. The equations of the model describe the fluid flow, the diffusion phenomenon, inertia and direct intercept mechanisms to describe the filtration processes. The simulations show a good agreement between the experimental data and the model. This model is able to supply information about the filtration efficiency of the exhaust gas particles and the pressure drop along the solid foam filter, consequently it can be used in order to estimate the catalytic activity (i.e. the total number of soot particles consumed by the catalytic reaction).