01796nas a2200205   4500008004100000022001400041245007700055210006900132260007300201300001200274490000800286520108400294653002001378653000801398653001701406653002101423100002201444700001601466856010801482       2006                        eng d  a0011-916400aComparison of flow structures in spacer-filled flat and annular channels0 aComparison of flow structures in spacerfilled flat and annular c  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcMAY  a236-2440 v1913 a<p>Spacers are designed to create directional changes in the flow through membrane modules. Such secondary flow structures reduce concentration polarization and membrane fouling. Obviously, type of the spacer used in membrane modules strongly influences the resulting flow and therefore performance of the module. In this work, we have modeled detailed fluid dynamics of spacer filled channels by using the `unit cell' approach. The validated computational fluid dynamics (CFD) model was used to evaluate performance of certain spacer shapes and compare the resulting fluid dynamics in flat and curved channels. The simulations show that fluid flow behavior in a spacer-filled flat and a spiral channel was not significantly different. This means that pressure drops and mass transfer coefficients measured in flat channels may provide adequate guidelines, which would also be valid for spiral-wound modules. The results presented in this work will have significant implications for identifying improved spacers with higher propensities to reduce fouling in membrane modules.</p>10aannular channel10aCFD10aflat channel10amembrane spacers1 aRanade, Vivek, V.1 aKumar, Anil  uhttps://library.ncl.res.in/content/comparison-flow-structures-spacer-filled-flat-and-annular-channels-0