Effect of the baffle design and orientation on the efficiency of a membrane tube

- We examine the effect of a new baffle design on the efficiency of a membrane tube.
- Two different orientations of hemispherical baffles are used, namely: right and left.
- Two values of the carbonate calcium suspensions are used: 5 and 10 g/L.
- The axial velocity, stream function, wall shear stresses and turbulent characteristics are determined.

A numerical investigation is carried out to examine the effect of a new baffle design in a membrane tube on the hydrodynamics and filtration efficiency. Two different orientations of hemispherical baffles named as RO baffle for the Right Orientation and LO baffle for the Left Orientation, respectively, are explored. Two values of the carbonate calcium suspensions are used: 5 and 10 g/L. The axial velocity, stream function, static pressure, wall shear stresses and turbulent characteristics are the physical parameters utilized to evaluate the filtration performance. The obtained results showed that the presence of an array of hemispherical baffles can develop the local shear stresses on the membrane surface and create the fluid eddy movement which enhances considerably the filtration performance. When the feed concentration is 5 g/L and in a comparison with the unbaffled tubes, the RO and LO cases achieved an increase in the filtration flux rate by 57% and 64%, respectively. For the second feed concentration (10 g/L), the enhancements are 85% and 96% for the RO and LO cases, respectively. In a comparison between the LO and RO cases, the LO baffle gives the best performance. Our results were compared with experimental data and a satisfactory agreement has been found.