Geometric Effects of Wall Flow Monoliths on Pressure Drop
Published August 22, 2005 by Society of Automotive Engineers of Korea in South Korea
Since wall flow monoliths which have become the most common substrate for diesel particulate filters have high flow resistance genetically because of their alternatively plugged channels, it is very important to reduce pressure drop during designing a diesel particulate filter with the wall flow monolith. The geometric factors such as diameter, length and volume are basic parameters to be considered to reduce pressure drop. In this study, the effect of the geometric factors has been studied in terms of pressure drop with an air flow test rig and an analytical method. Various silicon carbide filters with different volume, frontal area and length have been tested on the flow rig. The main factors for pressure drop were turned out to be the frontal area and length of filters while there is no definite correlation between volume and pressure drop. The cold air flow rig test data could be used for predicting actual back pressure during engine running with a reasonable accuracy by using Reynolds analogy.