Filtration in Pore Networks

The analysis of researches of mechanism of formation of profile of the processed surfaces is resulted polishing taking into account influence of particulate matters, contained in a lubricating-cooling liquid (LCL). For the exception of origin of being slightly burnt at polishing and diminishing of roughness of surface, muddy liquids must be purged from the particulate matters of metal-workingness. Utillizing of filtration for cleaning of technological liquids most effectively, because during filtration through the layer of porous materials it is possible to attain complete extraction of particulate matters from liquids. However features of structure of porous space generation row of the specific phenomena, arising up at motion of liquids in ductings of porous environment. A research purpose is a study and establishments of conformity to the law of process of filtration of technological liquids through porous materials. During filtration of technological liquids through the layer of porous materials the porous environment of filter partition is deformed with a change its porosity. A change porosity takes a place due to diminishing of volume of pores of porous space, because particulate matters together with a liquid get to the pores of ductings of porous space and hang up in them. In the examined model, the process of filtration of slime suspensoids flows with the permanent stoppering of pores of filter partition. Conformities to the law of process of filtration of technological liquids are investigational through porous materials. During filtration of liquid with particulate matters the porous environment of filter partition is deformed with a change its porosity. The conducted researches allowed to expose and study conformities to the law of process of filtration and set the law of change porosity of porous environment. On the basis of the set law differential equalization which allows at the set initial and scope conditions to decide the task of filtration of liquid through the layer of particulate matters of the deformed porous environment of filter partition is shown out.

Porous carbon materials based on MOFs in microwave absorbing

Chapter 26 - Porous Materials from Polybenzoxazine

This paper concerns the use of network principles to study displacement phenomena in porous media. The information presented is for equal-viscosity, equal-density miscible displacements. The paper explains the reasons for using an interconnected network of capillary tubes to model the interconnected network of pores in a reservoir rock. A method is presented for defining the heterogeneity of a presented for defining the heterogeneity of a network of tubes based on tube-size and tube-location distribution functions. A technique is described for constructing a network whose heterogeneity models the heterogeneity of pores in a reservoir rock. The use of networks to provide information which can be used in the solution of reservoir engineering problems is illustrated with example calculations of the effect of heterogeneity on fingering, breakthrough, and selective plugging in linear systems, and the effect of heterogeneity on areal sweep efficiency in a five-spot pattern. Introduction Oil in a reservoir is contained in an interconnected three-dimensional network of pores. Direct evidence of the nature of this network of pores comes from examination of petrographic thin sections and three dimensional Scanning Electron Microscope (SEM) pictures of the pores. The SEM pictures show that the pores in a reservoir rock are channels through which flow can occur. These channels have highly irregular configurations so irregular that it is not practical at this time to calculate flow behavior through individual channels or through the interconnected network of the channels. It is practical, however, to use a computer to calculate flow behavior in an interconnected network of capillary tubes and several investigators have studied the problem of using a network of tubes to model a network of pores. pores. Fatt pioneered the idea of using a network of cubes model for reservoir engineering studies. He demonstrated that capillary pressures, relative permeabilities, and electrical resistivities permeabilities, and electrical resistivities calculated for a network model have the same characteristics as those measured for real pores in reservoir rocks. From this, Fatt concluded that the network of tubes is a valid model of real porous media. Rose reinforced Fatt's conclusion and showed that computers can be used to study the displacement characteristics of networks and to obtain results "…which can be supposed to have a direct bearing on the mechanics of petroleum recovery…" This paper takes two steps beyond the work of Fatt and Rose. First, it describes a technique for constructing a network whose heterogeneity models the heterogeneity of natural pores. This is done by matching calculated equal-viscosity miscible displacement behavior in the network with measured behavior in a laboratory core. Second, it illustrates the use of the network model for calculating the effects of heterogeneity on fingering, breakthrough, and plugging in linear systems and areal sweep efficiency in a five-spot pattern. The networks used in the studies in this paper consist of several hundred interconnected capillary tubes of different sizes. Four different types of connections or configurations were investigated and are shown below. These configurations are discussed in detail later in the paper. SPEJ P. 99

Chapter 6 - Platinum group-based metal-organic frameworks (MOFs) nanocomposites

To accelerate the development of advanced power plants, DOE's Vision 21 program identified the need for an integrated suite of software tools that could be used to simulate and visualize new plant concepts. Existing process simulation software did not meet this objective of virtual-plant simulation. Sophisticated models of many individual equipment items are available; however, a seamless coupling capability that would integrate the advanced equipment (component) models to the process (system) simulation software remained to be developed. The inability to use models in an integrated manner causes knowledge loss (e.g., knowledge captured in detailed equipment models is usually not available in process simulation) and modeling inconsistencies (e.g., physical properties and reaction kinetics data in different models are not the same). A team consisting of Fluent Inc., ALSTOM Power Inc., Aspen Technology Inc., Intergraph Corporation, and West Virginia University, in collaboration with the National Energy Technology Laboratory (NETL), addressed this challenge in a project performed over the period from October 2000 through December 2004. In this project the integration of the cycle analysis software was based on widely used commercial software: Aspen Plus{reg_sign} for process simulation and FLUENT{reg_sign} for computational fluid dynamics (CFD) modeling of equipment items. The integration software was designed to also include custom (in-house, proprietary, legacy) equipment models that often encapsulate the experience from the many years of designing and operating the equipment. The team adopted CAPE-OPEN (CO) interfaces, the de facto international standard for communication among process models, for exchanging information between software. The software developed in this project is the first demonstration of the use of CO interfaces to link CFD and custom equipment models with process simulators. New interface requirements identified during this project were communicated to the CO standard developers. The new software capability was designed to make the construction of integrated models fast and integrated simulations robust and user-friendly. Configuration wizards were developed to make CFD and custom models CO-compliant. An Integration Controller and CFD Model Database were developed to facilitate the exchange of information between equipment and process models. A reduced order model (ROM) framework and a solution strategy capability were incorporated in the Integration Controller to enable a flexible trade-off between simulation speed and complexity. A CFD viewer was developed so that process engineers can view CFD results from the process simulator interface.

Porous materials are very efficient in absorbing mechanical energy, for instance, in combined armor, in order to improve the anti-ballistic protection characteristics. In the present study, porous titanium-based structures were manufactured via three different powder metallurgy methods using titanium hydride (TiH2) powder, which provided activated sintering, owing to dehydrogenation. The emission of hydrogen and shrinkage of powder particles on dehydrogenation also added an additional potential to control the sintering process and create desirable porosities. TiH2 powder was sintered with additions of NaCl or ammonium carbide as pore holding removable agents, while highly porous Ti-Al structures were formed via liquid phase reactive sintering of TiH2 and Al powders. The microstructures and porosities of sintered dehydrogenated titanium and Ti-Al structures were comparatively studied. Mechanical characteristics were evaluated using compression testing with strain rates varying from quasi-static to high levels. The resonant frequency method was also employed to determine damping parameters and elastic modulus of these materials. All testing methods were aimed at characterizing the energy-absorbing ability of the obtained porous structures. The desired strength, plasticity and energy-absorbing characteristics of porous titanium-based structures were assessed, and the possibilities of their application were also discussed. Based on the obtained results, it was found that porous titanium materials produced with the use of ammonium carbonate showed promising energy absorption properties.

The motion and interaction of discrete bubbles in porous materials is studied numerically using a network model. The goal is to extend analytical results for the motion of bubbles through a single straight tube to a more ‘realistic’ geometry for porous materials, modeled here as a planar network of straight tubes of different radii. The problem is characterized by two dimensionless parameters, the capillary number (Ca) and the volume fraction of bubbles (φ); results are characterized by determining the effective permeability of the network and the mean residence time of bubbles in the material. The simulations indicate that at low volume fraction most of the bubbles follow a limited number of high-flow pathways through the network. In this case the predictions of our simulations can be approximated by a simple analytical model. Bubbles interact with each other because their presence changes the local resistance to flow in individual tubes. As φ increases, interactions between individual bubbles become important resulting in a wider range of residence times in the porous material.

Design controllable TPMS structures for solar thermal applications: A pore-scale vs. volume-averaged modeling approach

Porous materials as electrode materials have demonstrated numerous benefits for high-performance Zn-ion batteries in recent years. In brief, porous materials as positive electrodes provide distinctive features such as faster electron transport, shorter ion diffusion distance, and richer electroactive reaction sites, which improve the kinetics of positive electrode reactions and achieve higher rate capacity. On the other hand, the porous structures as negative electrodes also exhibit electrochemical properties possessing higher surface area and reducing local current density, which favors the uniform Zn deposition and restrains the dendrite formation. In view of their advantages, porous electrode materials for ZIB are expected to be extensively applied in electric and hybrid electric vehicles and portable electronic devices. In this review, we highlight the methods of synthesizing porous electrode materials and discuss the mechanism of action of porous structures as electrodes on their electrochemical properties. At the end of this review, the perspectives on the future development of porous materials in the field of electrochemical energy storage are also discussed.

Advances in Emerging Crystalline Porous Materials.

Software process simulation (SPS) has become an effective tool for software process management and improvement. However, its adoption in industry is less than what the research community expected due to the burden of measurement cost and the high demand for domain knowledge. The difficulty of extracting appropriate metrics with real data from process enactment is one of the great challenges. We aim to provide evidence‐based support of the process metrics for software process (simulation) modeling. A systematic literature review was performed by extending our previous review series to draw a comprehensive understanding of the metrics for process modeling following our proposed ontology of metrics in SPS. We identify 131 process modeling studies that collectively involve 1975 raw metrics and classified them into 21 categories using the coding technique. We found product and process external metrics are not used frequently in SPS modeling while resource external metrics are widely used. We analyze the causal relationships between metrics. We find that the models exhibit significant diversity, as no pairwise relationship between metrics accounts for more than 10% SPS models. We identify 17 data issues may encounter in measurement and 10 coping strategies. The results of this study provide process modelers with an evidence‐based reference of the identification and the use of metrics in SPS modeling and further contribute to the development of the body of knowledge on software metrics in the context of process modeling. Furthermore, this study is not limited to process simulation but can be extended to software process modeling, in general. Taking simulation metrics as standards and references can further motivate and guide software developers to improve the collection, governance, and application of process data in practice.

The investigation of porous materials is pivotal to the advancement of science and technology. Polyurethane, a versatile and high-performance material, holds extensive application potential across various industries. This exceptional polymer exhibits unique chemical structures and superior performance characteristics, earning it the moniker of "Transformers" in the material world. Porous materials are characterized by their pore structure, which confers advantages such as high porosity, large specific surface area, low thermal conductivity, and lightweight properties. Porous polyurethane materials integrate the attributes of polyurethane with a porous architecture, demonstrating significant potential for diverse applications. This article first delineates the structure and properties of porous polyurethane materials, followed by an overview of synthesis methods including solution casting, sacrificial templating, phase separation, freeze drying, gas foaming method, electrospinning, and 3D printing method. This paper highlights the research status of on porous polyurethane materials in rigid and flexible foams, smart temperature-controlled textiles, biomedicine, electrochemistry, and oil-water separation, as well as electromagnetic shielding and piezoresistive sensors. Finally, this article addresses the challenges encountered in the preparation and application of porous polyurethane materials and provides insights into prospective development trends.

The role of Cr in the reactive synthesis of porous FeAlCr intermetallic compounds

Processing of non-random porous ceramic structures via fused deposition process is discussed. structures are characterized experimentally and statistically based on their compressive strength. Finite element modeling is used to understand the effect of stress concentration leading to the strength degradation ofthese brittle elastic solids. Introduction Porous ceramic materials are of significant technological interest due to their applications in molten metal filters, light weight core for sandwich panels, radiant burners, catalyst supports, sensors and bone grafts [1-2]. The porosity may be needed in the structures to reduce the weight of the structure at the non-critical areas, to increase the activity of the ceramics by increasing surface area or to separate the wanted from the unwanted materials during filtering. But in all the cases, a better control of the pore geometry and improvements of the mechanical properties ofthe porous structures are important to improve the reliability ofthe structures. Various processing techniques have been utilized to fabricate porous ceramic materials. Replamineform process was utilized to fabricate porous bioceramic implants to duplicate the macroporous microstructures of corals that have interconnected pores [3]. Porous alumina ceramics have been fabricated using pore former or foaming agent that evolves gases during sintering at elevated temperatures [4]. Porous Hydroxyapatite (HAp) ceramic blocks were also fabricated using HAp slurry mixed with foaming agent followed by sintering at elevated temperature [5]. Shrout et al. and Rittenmyer et al. [6-7] reported fabrication of 3-3 piezocomposites using a mixture of volatilizable plastic spheres and PZT powder, in a process known as BURPS (BURned-out Plastic Spheres). Unfortunately, all of these processes form structures with randotnly arranged pores with a wide variety of sizes and have limited flexibility to control pore volumes and porosity distribution in the final structure. In this paper, we discuss about porous ceramics with non-random pore volumes, shapes and sizes, which have been processed using solid freeform fabrication (SFF) methods. SFF offers tremendous flexibility in varying the porosity parameters which controls the strength ofthese ceramic structures as well. Theoretical and experimental characterization of porous materials is not new and several theories have already been postulated to characterize the mechanical strength of polyct:ystalline porous ceramics. These theories to characterize the mechanical strength can be classified into three broad categories: (1) reduction in cross-section area approach, (2) stress concentration approach and (3) effective flaw size approach. Most of these studies in predicting the porositystrength relationship have been limited to the fitting capability of the equations towards the available experimental data and no attempt has been made to quantitatively access the effects of porosity parameters on the strength degradation ofthe porous ceramic structures.