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In recent years, the demands of the industry to enhance filtration performance increased the use of digital tools to design new filter element shapes. Computer-Aided Design (CAD) is crucial, not just for detailed designs but also for broader simulations analyzing flow and filtration within filters.

However, conducting systematic simulations across different designs requires creating and importing CAD data into the CAE engine one by one, which can be time-consuming. To tackle this, we present a digital workflow to generate cylindrical pleat structures with variations in pleat count, thickness, and the number of porous layers in our own CAE engine, GeoDict. The creation and assessment of pleat structures is simplified, enabling a streamlined evaluation of the impact of their characteristics on key filtration parameters.

In addition to that, computational resources and simulation time of filter flow performance are reduced significantly with a multi-scale approach. Instead of simulating each fiber individually, porous layers are used, incorporating effective parameters as input parameter. These input parameters are derived from microscale simulations or flat sheet experiments.

In the presented study different filter structures are simulated to identify the most efficient configuration to minimize pressure drop while maximizing filter area. Since only the most promising prototypes undergo further physical evaluation, the result is a great reduction of ... Moreover, cloud platforms enable simultaneous simulations of various designs and differing flow rates, enhancing overall productivity.

Adsorption-based processes play a crucial role in reducing environmental pollution and eliminating harmful substances. Common filter media materials, like activated carbon, zeolites, and metal-organic frameworks, are used to effectively purify fluids and gases for applications ranging from water treatment to air purification. A way to measure and classify the quality of adsorption filter media is to look at breakthrough curves. A breakthrough curve shows the concentration of the adsorbate in the filtrate behind the filter media, and breakthrough occurs in the moment when adsorbate shows up in the filtrate.

In carbon capture, adsorption is vital to trap and store CO₂ emissions from industrial activities and power generation, preventing their release into the atmosphere. The CO₂ may be stored or used in processes like enhanced oil recovery or synthetic fuel production. However, determining breakthrough curves for a specific contaminant often requires time-consuming and costly experimental procedures.

In this context, the use of simulations allows to precisely control experimental parameters such as temperature, pressure, and surface properties to investigate their effects on adsorption behavior – gaining important insights into the microstructure to develop next-generation filter media.

In this study, we introduce the efficient simulation of adsorption on the filter media scale using GeoDict, a powerful tool for digital material development and prototyping. The approach is to calculate the molecular movement of particles and to solve for the adsorption equilibrium step by step using Langmuir and Toth adsorption isotherms. The simulation delivers breakthrough curves for arbitrary contaminants. The method is validated against experimental data from Coker and Knox, 2014 [1].

Future developments seek to include additional adsorption isotherms and improve simulation speed. Overall, these new simulation features provide new capabilities for product development in the field of adsorption-based filtration applications.

Electret filters find widespread application across various industries due to their exceptional filtration efficiency. These filters operate on the principle of electrostatic attraction between charged fibers and particles, electrophoresis and dielectrophoresis. However, research on electret filter media faces numerous challenges and complexities, such as charge stability over time, charge uniformity, and distribution of charges, particularly on the fibers.

In this context, numerical simulations play a crucial role in deepening the understanding of the fundamental mechanisms governing the behavior of electret filter media. They provide valuable insights into the complex interplay among electrostatic forces, airflow dynamics, and particle behavior, aspects not easily observable or measurable through experiments.

For the simulations of particulate filtration in filter media and elements, the FilterDict module of GeoDict stands out as a powerful software tool. Its capabilities to perform direct numerical simulations of electrophoresis are currently being enhanced in the framework of the ElekSim project, funded by the German Federal Ministry for Economic Affairs and Climate Action (BMWK). The overall objective of this project is to develop a new simulation environment focusing specifically on electret filters with the aim to streamline the optimization of electret filter media and to validate it against measurements. So far we have the comparison of simulation results of real filter media originating from different charging processes such as hydro charging, corona charging and triboelectric charging. The FilterDict developments include simulating diverse charge distributions in both particles and fibers, adding dielectrophoresis to existing electrophoresis capabilities, and tracking surface charge decay in electret filter media over time.

The initial verification of this simulation methodology is compared against results from Fluent® on a single fiber and simple multi-fiber models and includes a comparison of the computed filter efficiency across a given particle size distribution. Next, the new features will be validated against measurements on provided µCT scans. To investigate the effects of electrostatic charge on the filter efficiency, the filter media are additionally discharged using isopropanol to expose the pure mechanical filtration characteristics.

These insights will allow drawing new conclusions for the design of innovative next-generation electret filter media with different charge distribution methods, structural configurations, and improved charge stability.