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Surface-patterned membranes are becoming increasingly attractive for reducing fouling in membrane processes for water treatment. In this review article, literature on simulations of physically surface-patterned membranes is reviewed, with emphasis on the various factors affecting their anti-fouling performance. Associated computational techniques, including computational fluid dynamics and Brownian dynamics, are discussed. Key parameters discussed in the literature include the dimensions of the membrane (height, width), the velocity and direction of the fluid flow, the size of the particles, and the pattern size (height, width, and pitch). The key observables are the shear stress and velocity streamlines at various points, especially the pattern apex and valley regions, with an un-patterned membrane as a point of comparison in studies. The review concludes that the pattern dimensions have the most significant influence on the anti-fouling performance. Also, the effect of particle size to membrane pattern ratio on the extent of particle deposition on the membrane (fouling activity) can be explained by understanding the shear stress distribution around the membrane. [ABSTRACT FROM AUTHOR]

The world is constantly challenged regarding managing environmental and ecological contamination due to human and industrial activities. This is because of the constant threat posed by pollution. Nowadays, membrane‐based technology is a growing field, making practically all the separation of foulant from wastewater possible. The membrane fouling resulting from the interaction between the foulant and the membrane surface presents a challenge for the technology in maintaining performance over extended periods of operation. As a result, there is a rising interest in research focusing mainly on creating patterned membrane surfaces that reduce fouling and effectively enhance the surface area. This article comprehensively overviews the most recent and cutting‐edge techniques that can be applied to modify and construct high‐performance patterned membranes suitable for ultrafiltration, microfiltration, nanofiltration, and reverse osmosis (UF, MF, NF, and RO) water purification processes. In this study, recent developments in membrane material are dissected, focusing on methods for improving surface chemistry, structure, and hydrodynamics, as well as the consequences of these characteristics on filtering performance. [ABSTRACT FROM AUTHOR]

The study of microswimmers in viscoelastic fluids is important due to their essential role in many biological systems and various industrial and medical applications. This review article summarizes the behavior of microswimmers in complex viscoelastic fluids. Interestingly, both an increase or decrease in the speed and the power efficiency of microswimmers may be observed depending on the swimming pattern and the rheology of the polymeric fluid. First, it introduces the continuum frameworks for a complex fluid in which the microswimmers are present. This study briefly discusses how the reciprocal motion can propel a swimmer in a viscoelastic fluid contrary to the scallop theorem. This is followed by a section on different types of individual swimmers and their theoretical framework. A finite‐sized swimming sheet can show the resonance effect when relaxation time matches the characteristic time of the swimming. Lastly, progress on the topic of squirmers in the complex environment is presented, and it is seen that the interaction of the squirmer with the complex fluid is unpredictable. [ABSTRACT FROM AUTHOR]