Filter Vessel Design Considerations

Filtration vessel design has a large impact on filtration system performance. Poor designs with abrupt changes in flow direction and variable cross sectional changes increase the pressure drop across the vessel. In severe cases, this can increase the systems annual operating costs by as much as 25%. Vessel designs with too many dead flow areas (shown in dark blue) cause stagnant areas where bacteria can grow. To obtain optimum efficiency always try to minimize variable cross sections and obstructions in the flow path.

In this example (contrary to common belief) a contoured head on the vessel actually hinders rather than helps. The flat head design flows 15% more efficient than the curved head. This correlates to an annual energy savings of 15%. The reason is not that the contour was a poor idea but because it was incorrectly positioned. Modifying the contour will make the curved head more efficient than the flat.

Flat Cover Design	Contoured Head Cover Design

CFD velocity data plots courtesy of Sigma Design Company

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