Digitální dvojče úpravny vody – vývoj a využití v praxi
Sochorová, Helena; Andreides, D.; Hložanka, F.; Prokopová, Michaela; Stejskal, O.; Chalupa, L.; Šmejkalová, P.; Dolejš, P.
2023 - Czech
Příspěvek představuje zkušenosti s vývojem digitálního dvojčete pro optimalizaci řízení ÚV v rámci pilotního projektu v lokalitě Železná Ruda. Digitální dvojče se skládá ze dvou komponent, a to digitální dokumentace v objektové architektuře zpracované postupem reverzního inženýrství, která je datově propojená s reálnou fyzickou infrastrukturou (virtuální replika infrastruktury) a ze simulačního nástroje na základě matematického modelu anebo neuronové sítě (simulace procesu úpravy vody). Obě komponenty jsou uživateli přístupné přes webovou aplikaci, ve které lze volit ze tří provozních stavů (monitoring reálného stavu - defaultní, simulace scénářů provozních nastavení a predikce tlakové ztráty). The contribution presents experiences with the development of a digital twin for optimizing the control of the DWTP within the pilot project in the Železná Ruda locality. The digital twin consists of two components, i.e. digital documentation in the object architecture processed by the reverse engineering process, which is data-connected with the real physical infrastructure (virtual replica of the infrastructure) and a simulation tool based on a mathematical model or a neural network (simulation of the water treatment process). Both components are accessible to the user via a web application, in which one can choose from three operating states (monitoring of the real state - default, simulation of scenarios of operating settings and prediction of pressure loss).
Keywords:
digital twin; water quality; control optimization; reverse engineering; water treatment
Available at various institutes of the ASCR
Digitální dvojče úpravny vody – vývoj a využití v praxi
Příspěvek představuje zkušenosti s vývojem digitálního dvojčete pro optimalizaci řízení ÚV v rámci pilotního projektu v lokalitě Železná Ruda. Digitální dvojče se skládá ze dvou komponent, a to ...
Analýza pohybu bimodální suspenze u stěny potrubí
Chára, Zdeněk; Matoušek, Václav; Novotný, Jakub; Konfršt, Jiří
2022 - Czech
V článku je pozornost zaměřena na proudění bimodálních suspenzí, kdy je kombinována hrubá frakce s jemnou s výsledným efektem snížení celkových tlakových ztrát. S využitím metod PIV a PTV je analyzováno proudění u dna potrubí. Tímto přístupem byly získány rychlosti jak bimodální směsi, tak také rychlosti jednotlivých částic hrubé frakce. Rychlosti hrubých částic byly vyšší než rychlosti jemné frakce. In the paper, the attention is focused on the flow of bimodal suspensions, where the coarse fraction is combined with the fine fraction with the resulting effect of reducing the total pressure losses. Using the PIV and PTV methods, the flow at the bottom of the pipe is analyzed. Using this approach, the velocities of both the bimodal mixture and the individual particle velocities of the coarse fraction were obtained. The velocities of the coarse particles were higher than the velocities of the fine fraction.
Keywords:
bimodal suspensions; PIV method; PTV method
Available on request at various institutes of the ASCR
Analýza pohybu bimodální suspenze u stěny potrubí
V článku je pozornost zaměřena na proudění bimodálních suspenzí, kdy je kombinována hrubá frakce s jemnou s výsledným efektem snížení celkových tlakových ztrát. S využitím metod PIV a PTV je ...
Experimental validation of granular flow kinetic theory under turbulent flow conditions
Haidl, Jan; Chára, Zdeněk; Matoušek, Václav
2022 - English
The mixed classical and extended kinetic theory of granular ows is used for modeling the characteristics of particles-water turbulent sheet ow. The open-source solver sedFoam v3.1 is used for the 1-D and 2-D ow simulations. The simulation results are compared to the experimental data measured in the open channel. After that, the simulation parameters are optimized to achieve the best possible agreement between the simulation and the experimental results. The unsatisfactory performance of the KT models and the observed simulation instabilities are discussed.
Keywords:
kinetic theory; granular flow; sedFoam
Available at various institutes of the ASCR
Experimental validation of granular flow kinetic theory under turbulent flow conditions
The mixed classical and extended kinetic theory of granular ows is used for modeling the characteristics of particles-water turbulent sheet ow. The open-source solver sedFoam v3.1 is used for the 1-D ...
Antibacterial electrospun membrane prepared from poly(vinylidene fluoride)-co-hexafluoropropylene with lauric acid monoacylglycerol
Zelenková, Jana; Peer, Petra; Pleva, P.; Janalíková, M.; Sedlaříková, J.; Filip, Petr
2021 - English
The aim of this study was to prepare an antibacterial nanofibrous membrane using electrospinning technique. The nanofibrous membranes were spun from polymer solution of poly(vinylidne fluoride)-co-hexafluoropropylene (PVDF-co-HFP) dissolved in N,N´-dimethylformamide. Monoacylglycerol of lauric acid (MAG C12) was used as an antimicrobial agent at the concentrations ranging from 1 to 3 wt%. The impact of MAG C12 incorporation on the rheological, structural and antibacterial properties was investigated. The rheological tests of polymer solutions, as steady shear and oscillatory shear, proved that addition of MAG C12 changed marginally rheological quantities such as viscosity, elastic (storage) and viscous (loss) moduli. Measurement of mean nanofibres diameter indicated a slight decrease with increasing MAG C12 concentration. Antimicrobial activity of PVDF-co-HFP nanofibre membranes with incorporated MAG C12 against Gram-positive bacteria Staphylococcus aureus and Gram-negative Escherichia coli was studied. An antibacterial activity was revealed for the samples containing MAG C12 at all concentrations against Gram-positive bacteria Staphylococcus aureus by the disk diffusion method.
Keywords:
nanofibres; electrospinning; antibacterial memrane; rheology; polymer solution
Available at various institutes of the ASCR
Antibacterial electrospun membrane prepared from poly(vinylidene fluoride)-co-hexafluoropropylene with lauric acid monoacylglycerol
The aim of this study was to prepare an antibacterial nanofibrous membrane using electrospinning technique. The nanofibrous membranes were spun from polymer solution of poly(vinylidne ...
Magnetic properties of electrospun polyvinyl butyral/Fe2O3 nanofibrous membranes
Peer, Petra; Cvek, M.; Urbánek, M.; Sedlačík, M.
2020 - English
In this contribution, magnetic Fe2O3 nanoparticles (MNPs) were successfully incorporated into the polyvinyl butyral (PVB) nanofibrous membranes using the electrospinning process. The effects of the MNP concentration on the morphology of the nanofibres and their magnetic properties were investigated. Scanning electron microscopy and transmission electron microscopy confirmed their concentration-dependent, yet uniform diameter, and the presence of well-embedded MNPs inside the PVB nanofibres. The magnetic properties of the PVB/MNP membranes were studied using the vibrating-sample magnetometry. The saturation magnetization increased from 6.4 to 45.5 emu/g as the MNP concentration in the feedstock solution increased from 1 to 15 wt%. The fabricated PVB/MNP nanofibrous membranes possessed the ability to respond to the external magnetic fields, which determines their potential in the development of the advanced smart textiles.
Keywords:
electrospinning; polyvinyl butyral; nanofibres; magnetic properties
Available at various institutes of the ASCR
Magnetic properties of electrospun polyvinyl butyral/Fe2O3 nanofibrous membranes
In this contribution, magnetic Fe2O3 nanoparticles (MNPs) were successfully incorporated into the polyvinyl butyral (PVB) nanofibrous membranes using the electrospinning process. The effects of the ...
Flow behaviour of sand-water mixture in horizontal and inclined pipes
Vlasák, Pavel; Chára, Zdeněk; Matoušek, Václav; Kesely, Mikoláš; Krupička, Jan; Konfršt, Jiří; Mildner, Michael
2019 - English
Pipelines transporting slurries in different industrial applications often contain inclined sections. The effect of pipe inclination, slurry concentration and mean velocity on the flow behaviour, deposition\nlimit velocity, and internal structure of a settling slurry was studied in an experimental pipe loop of inner diameter D = 100 mm. The slurry consisted from water and a narrow particle size distribution sand of mean diameter d50 = 0.55 mm. The experiments focused on the effects of the pipe inclination on solids distribution and deposition limit velocity. The concentration distribution in pipe cross-section was studied with application of a gamma-ray densitometer. The study revealed the stratified flow pattern of the medium sand-water mixture in inclined pipe sections. Experimental results show that the degree of the slurry stratification decreased with an increasing angle of inclination in the ascending pipe sections. The slurry stratification affected the deposition limit velocity. Mean in situ concentration for the descending flow was always lower than that for the ascending flow. The deposition limit in ascending pipe, in comparison with that in a horizontal pipe, slightly increased up to inclination angle about +25°, and then remained practically constant. For negative pipe inclination over – 30° no deposition limit was observed.
Keywords:
slurry flow; inclined pipe; deposit limit velocity
Available at various institutes of the ASCR
Flow behaviour of sand-water mixture in horizontal and inclined pipes
Pipelines transporting slurries in different industrial applications often contain inclined sections. The effect of pipe inclination, slurry concentration and mean velocity on the flow behaviour, ...
Preparation and characterization of fibrous non-woven textile decorated by silver nanoparticles for water filtration
Peer, Petra; Polášková, M.; Mosnáček, J.; Sedlařiková, J.; Masař, M.
2019 - English
The environmentally friendly preparation of silver nanoparticles was proposed for the production of antibacterial non-woven textile used in water filtration. The silver nanoparticles were prepared by chemical reduction of silver nitrate using two environmentally friendly reducing agents, such as fructose or ascorbic acid. For comparison also commonly used reducing agent-sodium borohydride was used. The silver nanoparticles in various size and yield were produced by immersion of the plasma pre-treated polypropylene (PP) nonwoven textile in the colloidal solutions for different periods (35, 45 and 135 min). The morphology of the silver nanoparticles was characterized by SEM and EDX analysis. Additionally, the antibacterial activity of the silver decorated PP non-woven textile was evaluated by an agar diffusion test using both Gram-positive Staphylococcus Aureus and Gram-negative Escherichia coli. The results suggest that the type of the reducing agent has major effect both on the morphology of silver nanoparticles and the antibacterial activity.
Keywords:
silver nanoparticles; reducing agent; non-woven textile; antibacterial activity
Available on request at various institutes of the ASCR
Preparation and characterization of fibrous non-woven textile decorated by silver nanoparticles for water filtration
The environmentally friendly preparation of silver nanoparticles was proposed for the production of antibacterial non-woven textile used in water filtration. The silver nanoparticles were prepared by ...
Enkapsulace aktivních látek do přírodních polymerů
Sedlaříková, J.; Krejčí, J.; Krhovská, D.; Peer, Petra
2019 - Czech
Problematika enkapsulace je v posledních letech intenzivně studována za účelem docílení lepší vstřebatelnosti a prodloužení účinnosti aktivních látek. Podstatou práce bylo připravit směsi na bázi přírodních polymerů zeinu a chitosanu s aktivními látkami a sledovat vliv zastoupení jednotlivých složek na výsledné fyzikálně-chemické vlastnosti enkapsulační činnosti. Recently encapsulation has been intensively investigated to achieve a better absorbability and prolong efficiency of active agents. The aim of this work was to prepare the systems based on natural polymers zein and chitosan with active substances and observe the effect of individual components on the resultant physical and chemical properties of the encapsulation
Keywords:
encapsulation efficiency; zein; chitosan; active agents; thymol
Available at various institutes of the ASCR
Enkapsulace aktivních látek do přírodních polymerů
Problematika enkapsulace je v posledních letech intenzivně studována za účelem docílení lepší vstřebatelnosti a prodloužení účinnosti aktivních látek. Podstatou práce bylo připravit směsi na bázi ...
Měření rychlostních profilů nad depozitní vrstvou při dopravě suspenzí v potrubí
Chára, Zdeněk
2019 - Czech
Článek se zabývá měřením rychlostních profilů nad depozitní vrstvou při proudění suspenze pevných částic v potrubí. K měření byla použita optická metoda PIV s využitím vysokorychlostní kamery NanoSense. The paper deals with the measurement of velocity profiles above the deposit layer during the flow of solid particles in the pipeline. Optical PIV method using high speed NanoSense camera was used for the measurements.
Keywords:
PIV; suspension flow; granular temperature
Available at various institutes of the ASCR
Měření rychlostních profilů nad depozitní vrstvou při dopravě suspenzí v potrubí
Článek se zabývá měřením rychlostních profilů nad depozitní vrstvou při proudění suspenze pevných částic v potrubí. K měření byla použita optická metoda PIV s využitím vysokorychlostní kamery ...
Effect of pipe inclination on local concentration and flow behaviour of settling slurry
Vlasák, Pavel; Chára, Zdeněk; Matoušek, Václav; Kesely, Mikoláš; Konfršt, Jiří; Mildner, Michael
2019 - English
Settling slurry, consisted from narrow-graded sand of mean particle diameter 0.87 mm and water, was investigated on an experimental pipe loop of inner diameter 100 mm. The investigation was focused on the effect of the pipe inclination, slurry concentration, and velocity on concentration distribution, and deposition limit. The settling slurries tend to stratify, a layered structure is typical for a settling slurry flow. Slurry stratification is sensitive to pipe inclination, and differs for the positive and negative pipe inclination. Deposition limit increases with pipe inclination up to about 25°, and then remain nearly constant.
Keywords:
sand-water slurry; pipe inclination; concentration distribution; deposition limit
Available at various institutes of the ASCR
Effect of pipe inclination on local concentration and flow behaviour of settling slurry
Settling slurry, consisted from narrow-graded sand of mean particle diameter 0.87 mm and water, was investigated on an experimental pipe loop of inner diameter 100 mm. The investigation was focused on ...
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