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This allows tuning the design towards lower closing pressure or lower open state flow resistance compared to those of horizontal membrane microvalves.
Moreover, it is shown that the serpentine flow channels with 1.2 mm square bend size act successfully in preventing secondary flows internal thereby decreasing pressure drop about 90.6% compared to serpentine flow channels with a bend size of 0.8 mm.
Thus, it is important to select the most appropriate membrane (pore size, polymeric material, flux, etc.)
The ratio of length to diameter of the membrane module is of particular significance as it dictates the permeation rate for a specific pore size membrane.
Open accessJournal ArticleDOI
Mao Mao, John D. Sherwood, Sandip Ghosal 
40 Citations
When the membrane thickness is small, the flow rate agrees with that calculated using the reciprocal theorem.
Previously, obtained data indicate that the rate of membrane fouling (and thus membrane capacity) depends upon flow rate, thus making it difficult to extrapolate membrane capacities for large-scale, constant flow conditions from measurements in small-scale, constant pressure devices.
Obviously, type of the spacer used in membrane modules strongly influences the resulting flow and therefore performance of the module.
This paper presents a novel method to determine the flow rate and fluid resistance of membrane-type restrictors.
A uniform flow distribution will ensure that the complete membrane area is utilised.
Increasing the gas and liquid flow gives increased flux over the membrane, but also results in increased pressure drop in the module.

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