Perforated plates for fluid management: Plate geometry effects and flow regimes

• Pressure drop was determined by numerical simulation and confirmed by experimentation.
• The regimes of fluid flow were identified by the use of the Reynolds number as a metric.
• The downstream distance for the persistence of the flow disturbance caused by the presence of the plate was quantified.
• Plates of higher porosity gave rise to smaller pressure drops for all of the investigated flow regimes.
• The effect of plate thickness on pressure drop was found to be opposite for laminar flow than for turbulent flow.

Perforated plates are the preferred means of passive management of fluid flow proper and for convective heat transfer applications. The investigation reported here is a synergistic use of numerical simulation and experimentation to provide both in-depth fluid mechanic fundamentals and results for applications. The experimental results validated the choice of the turbulence model. A trio of dimensionless geometrical parameters was varied systematically, as was the Reynolds number to encompass both laminar and turbulent flows. For the laminar flow regime, higher pressure drops were associated with thicker plates and with the staggered-array hole pattern; higher porosities led to lower pressure drops. For the turbulent case, the thinner plate caused higher pressure drops as did the square-array hole pattern; also, the pressure drop was found to depend on the square of the Reynolds number, indicating the dominance of momentum-based losses. These trend reversals are attributable to the differences in separated-flow reattachment patterns for the different plate thicknesses.