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PurposeThe purpose of this paper is to present a study of the breaking process of composite membranes used in the water desalination. Temperature, fluid pressure and accumulate retained fluid are remarkable parameters, which are likely to damage these membranes.Design/methodology/approachIn this paper, the authors adopt the dynamics of a fiber bundle model to investigate the breaking process of composite membranes with fibres distributed parallel to the direction of fluid flow. The model is based on the fiber bundle model where the fibres are randomly oriented.FindingsThe obtained results show that the increase in the parameters leads to an avalanche rupture of the membrane fibre and also increases its porosity. Lifetime membranes exhibit an exponential and power law vs. the parameters.Originality/valueThe accumulation of the retained fluid has a great effect on membranes than the temperature and fluid pressure.

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The nanofiltration (NF) process becomes the most recently used technologies for the desalination of seawater and brackish water. The porous media transport properties are first related to the geometrical complexity of the product. However, the membrane transport models used in desalination process constitute approximatively the less understood process. The objective of this work is to address modeling and numerical study of the desalination process of the water and ions fluxes by using a porous membrane with nanoparticles. Our filtration system used is constituted by two different zones that the membrane sheets are sandwiched. The fluid undergoes a first simple filtration and a second NF process by the injected nanoparticles. The impacts of the permeability [Formula: see text] and porosity [Formula: see text] of the membrane under the effect of a pressure [Formula: see text] were discussed. Our findings are obtained in the framework of the dynamic Langevin approach based on the competitiveness between the stochastic process and dissipation. The results show that the performance of the rejection membrane is significant as the nanoparticle concentration decreases, and increases as a power law with the ratio of the viscosity of the salty fluid to the pure fluid.

This study numerically examines the fluid flow in porous media used in desalination. This topic is of significant current interest in the fields of science, engineering and technology, particularly in the process of water filtration. Moreover, in this work, we are attracted to correlation and diffusion process of the porous medium below the effect of permeability, dynamic pressure and friction coefficient. These parameters characterized the fluid flow in porous medium. To study numerically this phenomenon, many models have been proposed. However, we developed our investigation by using the Langevin dynamics model. Furthermore, this dynamic framework is based on Newton’s second law and Darcy’s law. Hence, we modeled the medium as a set of random diameters pores, which are dispersed randomly. The obtained results indicate that the average velocity time evolution presents an exponential profile with two different states: the first is transient and the second is permanent. The two regimes are separated by a cross-over time. Furthermore, time evolution exhibits an increasing profile versus the permeability, then it presents a decreasing profile versus the friction coefficient. Likewise, the diffusion process and correlation are tested for different parameters, especially the permeability and the dynamic pressure. We remark that the effective diffusion coefficient decreases exponentially with permeability and increases linearly with dynamic pressure. Hence, the fluid flow correlation in porous media presents a Gaussian function profile, with standard deviation function which increases exponentially with permeability.