Filters
total: 6020
-
Catalog
displaying 1000 best results Help
Search results for: OVERLAND FLOW
-
Experimental and numerical simulations of flow and heat transfer in heat exchanger elements using liquid crystal thermography.
PublicationW artykule przedstawiono założenia oraz sposób prowadzenia eksperymentu i obliczeń numerycznych wymiany ciepła w modelu wymiennika ciepła przy użyciu termografii ciekłokrystalicznej.
-
Method to solve the non-linear systems of equations for steady gradually varied flow in open channel network.
PublicationW artykule omówiono rozwiązanie systemu równań nieliniowych opisujacych przepływ ustalony wolnozmienny w sieci kanałów otwartych. Niewiadomymi są glębokości w poszczególnych przekrojach oraz natężenia przepływów w poszczególnych gałęziach systemu. Układ musi być rozwiązywany iteracyjnie. Klasyczne metody Picarda i Newtona mogą okazać się nieskuteczne ze względu na oscylacje rozwiązania w kolejnych iteracjach i związany z tym brak...
-
The pollutant transport equation for a steady, gradually varied flow in an open channel network: a solution of high accuracy
PublicationW pracy przedstawiono metodę rozwiązania jednowymiarowego równania adwekcji-dyfuzji opisującego transport zanieczyszczeń w warunkach przepływu ustalonego wolnozmiennego w sieci kanałów otwartych. Zastosowano technikę dekompozycji. Zlineoryzowane równanie adwekcji-dyfuzji rozwiązano stosując całkę Duhamela, zaś równanie zacierające człon źródłowy-metodą różnic skończonych. Metoda zapewnia bardzo dużą dokładność rozwiązania nawet...
-
Modelling of saturated, subcooled and post-dryout flow boiling with the energy dissipation based semi-empirical model
PublicationA comprehensive semi-empirical model for saturated, subcooled and post dryout heat transfer is presented based on considerations of energy dissipation in the flow. The fundamental hypothesis in the model is the fact that heat transfer during flow boiling can be treated as a sum of two contributions constituting the total energy dissipation in the flow, namely the energy dissipation due to the shearing flow without the bubbles and...
-
Lax-Wendroff and McCormack Schemes for Numerical Simulation of Unsteady Gradually and Rapidly Varied Open Channel Flow
PublicationTwo explicit schemes of the finite difference method are presented and analyzed in the paper. The applicability of the Lax-Wendroff and McCormack schemes for modeling unsteady rapidly and gradually varied open channel flow is investigated. For simulation of the transcritical flow the original and improved McCormack scheme is used. The schemes are used for numerical solution of one dimensional Saint-Venant equations describing free...
-
Numerical analysis of open channel steady gradually varied flow using the simplified saint-venant equations
PublicationFor one-dimensional open-channel flow modeling, the energy equation is usually used. There exist numerous approaches using the energy equation for open-channel flow computations, which resulted in the development of several very efficient methods for solving this problem applied to channel networks. However, the dynamic equation can be used for this purpose as well. This paper introduces a method for solving a system of non-linear...
-
Analysis of the bulk solid flow during gravitational silo emptying using X-ray and ECT tomography
PublicationW pracy przedstawiono wyniki pomiarów zmian koncentracji piasku bezkohezyjnego zachodzących w prostokątnym modelu silosu opróżnianym grawitacyjnie. Pomiary wykonano z zastosowaniem kontynualnego promieniowania rentgenowskiego oraz z użyciem tomografii pojemnościowej. Badania wykonano dla zróżnicowanego zagęszczenia początkowego piasku oraz różnego stopnia szorstkości ścian. Szczególny nacisk położono na zachowanie sie materiału...
-
Inverse method for 2D viscous flow design problem using stream-function coordinates for axisymmetric model
PublicationOpracowano metodę odwrotną dla przepływów lepkich nieściśliwych w osiowosymetrycznej konfiguracji. Użyto współrzędnych funkcji prądu mających tą właściwość, iż możliwe jest zastapienie jednej współrzędnej geometrycznej zmienną zależną od prędkości przepływu. W związku z czym możliwe jest rozwiązanie zadania projektowego. Metodę rozwiązano numerycznie dla przypadku testowego jak i pokazano możliwości metody dla bardziej skomplikowanego...
-
The influence of sterilization with EnbioJet Microwave Flow Pasteurizer on composition and bioactivity of aronia and blue-berried honeysuckle juices
PublicationIn this study, fruit juices that are rich sources of anthocyanins, obtained from aronia (Am. chokeberry, Aronia melanocarpa) and blueberry honeysuckle (Lonicera caerulea L. var. edulis) were used to examine the preservation of plant phytochemicals and bioactivity upon sterilization -either thermal, or with an EnbioJet microwave flow pasteurizer. The chemical properties verified included determinations of anthocyanins and other...
-
Electrohydrodynamic Secondary Flow and Particle Collection Efficiency in a One-sided Spike-plate Type Electrostatic Precipitator
PublicationIn this work, results of electrohydrodynamic secondary flow and particle collection efficiency measurements in an electrostatic precipitator under positive and negative voltage polarity are presented. The electrostatic precipitator had two plate collecting electrodes and a single spike discharge electrode. The spike tips were only on one side of the discharge electrode, therefore called a one-sided spike electrode. The electrohydrodynamic...
-
Application of subsurface vertical flow constructed wetlands to reject water treatment in dairy wastewater treatment plant
PublicationThe paper presents the effects of applying subsurface vertical flow constructed wetlands (SS VF) for the treatment of reject water generated in the process of aerobic sewage sludge stabilization in the biggest dairy wastewater treatment plant (WWTP) in Poland. Two SS VF beds were built: bed (A) with 0.65 m depth and bed (B) with 1.0 m depth, planted with reeds. Beds were fed with reject water with hydraulic load of 0.1 m d-1 in...
-
Preliminary results from HEDGEHOG REXUS project – A sounding rocket experiment on accelerations, vibrations and heat flow
PublicationDuring flight, a sounding rocket is subject to a unique environment - severe vibrations and substantial heat flux. In order to design payloads, precise measurement of these conditions is required. This paper presents preliminary results from HEDGEHOG REXUS Project, whose scientific goal was to characterise the thermal and dynamic environment of REXUS sounding rockets. For this purpose, two new sensors have been designed - mechanical...
-
EVALUATION OF LIQUID-GAS FLOW IN PIPELINE USING GAMMA-RAY ABSORPTION TECHNIQUE AND ADVANCED SIGNAL PROCESSING
PublicationLiquid-gas flows in pipelines appear in many industrial processes, e.g. in the nuclear, mining, and oil industry. The gamma-absorption technique is one of the methods that can be successfully applied to study such flows. This paper presents the use of thegamma-absorption method to determine the water-air flow parameters in a horizontal pipeline. Three flow types were studied in this work: plug, transitional plug-bubble,...
-
Experimental study on the selected aspects of bow thruster generated flow field at ship zero-speed conditions
PublicationThe paper presents the results of experimental study on the interaction between the bow thrusters understood as the flow field changes generated by bow tunnel thruster in deep water conditions operated as a single and twin units. The research was limited to zero-speed case for the ship dead in the water. The influence of the hull form and jet spread between the neighbouring thrusters for several combinations of the applied bow...
-
Cross-Lingual Knowledge Distillation via Flow-Based Voice Conversion for Robust Polyglot Text-to-Speech
PublicationIn this work, we introduce a framework for cross-lingual speech synthesis, which involves an upstream Voice Conversion (VC) model and a downstream Text-To-Speech (TTS) model. The proposed framework consists of 4 stages. In the first two stages, we use a VC model to convert utterances in the target locale to the voice of the target speaker. In the third stage, the converted data is combined with the linguistic features and durations...
-
Investigation of Liquid–Gas Flow in a Horizontal Pipeline Using Gamma-Ray Technique and Modified Cross-Correlation
PublicationThis article presents the application of the radioisotope absorption method in the study of two-phase water–air flow in a horizontal pipe. The measurement principle and the test stand are briefly described. The main part of the article presents the signal analysis methods applied to data obtained from scintillation detectors. Because these signals are mostly stochastic waveforms, they were analyzed statistically using the cross-correlation...
-
Improved finite element method for flow, heat and solute transport of Prandtl liquid via heated plate
PublicationIn the current study, a vertical, 3D-heated plate is used to replicate the generation of heat energy and concentration into Prandtl liquid. We discuss how Dufour and Soret theories relate to the equations for concentration and energy. In order to see how efectively particles, interact with heat and a solvent, hybrid nanoparticles are used. It does away with the phenomena of viscous dissipation and changing magnetic felds. The motivation...
-
Quantitative estimation of volume changes of granular materials during silo flow using X-ray tomography.
PublicationW artykule przedstawiono wyniki badań doświadczalnych nad zmianami objętościowymi materiału granulowanego podczas przepływu silosowego. Badania wykonano przy zastosowaniu tomografii rentgenowskiej. Wyniki porównano z wynikami doświadczalnymi przy zastosowaniu cyfrowej obróbki zdjęć płynącego materiału.
-
FE-investigations of granular flow in silos using an uncoupled ALE-formulation and a non-local hypoplastic model
PublicationArtykuł omawia wyniki naporu materiału sypkiego podczas przepływu w silosach z i bez wkładek. Obliczenia wykonano wykorzystując niepołączone sformułowanie ALE na bazie prawa sprężysto-plastycznego według Druckera-Pragera. Zbadano wpływ kształtu i położenia wkładki na wielkość naporu i rodzaj przepływu.
-
Micro-modelling of shear localization during quasi-static confined granular flow in silos using DEM
PublicationThe paper deals with the quasi-static confined flow of cohesionless sand in a plane strain model silo with parallel walls and a slowly movable bottom. Numerical modelling was carried out by the discrete element method (DEM) using spheres with contact moments to approximately capture a non-uniform shape of sand particles. Different initial void ratios of sand and silo wall roughness grades were employed. Regular triangular grooves...
-
Modelling of Capillary Pressure-driven Water Flow in Unsaturated Concrete Using Coupled DEM/CFD Approach.
PublicationSformułowano nowatorskie, połączone podejście do modelowania dwufazowego przepływu wody napędzanego kapilarami w nienasyconym betonie. Dzięki połączeniu metody elementów dyskretnych (DEM) z obliczeniową dynamiką płynów (CFD) w warunkach izotermicznych proces został zbadany numerycznie w mezoskali w warunkach dwuwymiarowych. Niewielkie próbki betonu o uproszczonej mezostrukturze cząstek poddano w pełni sprzężonym hydromechanicznym...
-
Dutch Crossing : a Journal of Low Countries Studies
Journals -
Fluid Mechanics and Hydraulics EE Msc sem. I r.a. 22/23
e-Learning CoursesBasic definitions. Physical properties of liquids. Forces acting on fluids. Hydrostatics - basic equations. Pressure on a flat and curved wall. Buoyancy. Archimedes' law. Balance of submerged bodies. The balance of floating bodies. Hydrodynamics. Hydrodynamic quantities. Continuity equation for the liquid stream. Bernoulli equation. Basic laws of hydrodynamics. Equation of mass behavior, preservation of the amount of motion, Bernoulli's...
-
Fluid Mechanics and Hydraulics EE Msc sem. I r.a. 23/24
e-Learning CoursesBasic definitions. Physical properties of liquids. Forces acting on fluids. Hydrostatics - basic equations. Pressure on a flat and curved wall. Buoyancy. Archimedes' law. Balance of submerged bodies. The balance of floating bodies. Hydrodynamics. Hydrodynamic quantities. Continuity equation for the liquid stream. Bernoulli equation. Basic laws of hydrodynamics. Equation of mass behavior, preservation of the amount of motion, Bernoulli's...
-
JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM
Journals -
Jacek Tomków dr hab. inż.
PeopleEducation:1. 2018 - Ph.D. of Technical Sciencesin field of Materials Engineeringthesis: Influence of underwater welding conditions on cold cracking of high strength low alloy steel 2. 2012 - Master of Science Engineer, Gdansk University of Technologyin the field of: Mechanical Engineeringwith specialization in: Manufacturing Engineering and Computer Aided Manufacturing Processesthesis: Non-destructive testing of welding joints...
-
Measurement of mass flow of viscous liquid through a Cylindrical Orifice under laminar flow (CylOr)
Open Research DataThe data was obtained as part of the project "Measurement of mass flow of viscous liquid through a Cylindrical Orifice under laminar flow (CylOr)", in which flow tests of hydraulic oil through a cylindrical orifice with a thickness of l = 25 mm and a throat b = 0.5 (diameter pipes D = 50 mm, orifice diameter d = 25 mm) on the test stand at the Department...
-
Liking low-status? Contextual and individual differences in attributional biases of low-status outgroup members
Publication -
Low-Voltage Low-Power Filters with Independent ω0 and Q Tuning for Electronic Cochlea Applications
PublicationAn acoustic second-order low-pass filter is proposed for filter banks emulating the operation of a human cochlea. By using a special filter structure and an innovative quality (Q)-factor tuning technique, an independent change of the cutoff frequency (ω0) and the Q-factor with unchanged gain at low frequencies is achieved in this filter. The techniques applied result in a simple filter design with low Q-factor sensitivity to component...
-
Long-term operation of Kickuth-type constructed wetland applied to municipal wastewater treatment in temperate climate
PublicationThe purpose of this paper is to discuss the problem of changes of effectiveness of Kickuth-type constructed wetland with subsurface flow applied to domestic wastewater treatment. This study is based on an example of a wetland 3000 m2 in surface, serving 800 inhabitants, located in Poland. The results of chemical analysis showed that after an initial year of ‘start-up time’, the efficiency of pollutant removal gradually increased...
-
The thermoluminescence glow curve and the deconvoluted glow peak characteristics of erbium doped silica fiber exposed to 70–130 kVp x-rays
Publication -
Marek Pszczoła dr hab. inż.
PeopleI am a Faculty member (Department of Highway and Transportation Engineering) at the Faculty of Civil and Environmental Engineering, Gdansk University of Technology, Poland). My main research interests include: low-temperature properties of asphalt mixtures, low temperature cracking assessment of pavement structures, road materials properties, thermal stress analysis, design of pavement structures, airfield design and analysis....
-
Uncertainty of mass flow measurement using centric and eccentric orifice for Reynolds number in the range 10,000 ≤ Re ≤ 20,000
PublicationThe article analyses the impact of the Reynolds number on the estimated uncertainty of the mass flow rate measurement using an orifice plate. The objects of the research were two types of orifices: centric (ISA) and eccentric, with the diameter ratio β = 0.5. Studies were performed by Monte Carlo simulation and experiments for Reynolds numbers in the range 10,000 ≤ Re ≤ 20,000. The obtained results have shown that for both orifice...
-
Combining X-ray tomogrpahy imaging and DEM simulations to investigate granular material flow during silo discharging
PublicationEven after few decades of research, the study of particle motion taking place during silo discharging hasn’t been fully addressed, both experimentally and numerically, because of nontrivial behaviors that occur during associated flow patterns. For instance, discrete element method (DEM) has shown good qualitative prediction potential of velocity profile, but, on the other hand, frequently failed to match quantitatively experimental...
-
Modelling of Objects Behaviour for Their Re-identification in Multi-camera Surveillance System Employing Particle Filters and Flow Graphs
PublicationAn extension of the re-identification method of modeling objects behavior in muti-camera surveillance systems, related to adding a particle filter to the decision-making algorithm is covered by the paper. A variety of tracking methods related to a single FOV (Field of Vision) are known, proven to be quite different for inter-camera tracking, especially in case of non-overlapping FOVs. The re-identification methods refer to the...
-
Does Post-Activation Performance Enhancement Occur during the Bench Press Exercise under Blood Flow Restriction?
Publication -
Modeling of heat and fluid flow in granular layers using high-order compact schemes and volume penalization method
Publication -
Does blood flow restriction influence the maximal number of repetitions performed during the bench press? A pilot study
Publication -
Multi-DBD plasma actuator for flow separation control around NACA 0012 and NACA 0015 airfoil models
PublicationIn this paper application of innovative multi-DBD plasma actuator for flow separation control is presented. The influence of the airflowgenerated by this actuator on the flow around NACA 0012 and NACA 0015 airfoil models was investigated. The results obtained from 2D PIVmeasurements showed that the multi-DBD actuator with floating interelectrode can be attractive for leading and trailing edge separation control.
-
A semi-empirical method for calculation of flow boiling heat transfer coefficients for conventional channels and small diameter tubes
PublicationW pracy przedstawiono rozważania na temat modelowania dwufazowego przepływu wrzącego w kanałach konwencjonalnych i w kanałach o małej średnicy. Przedstawiono modyfikację korelacji zaproponowanej wcześniej przez J. Mikielewicza na podstawie nowych danych eksperymentalnych, uzyskanych dla kanałów o małej średnicy. Bank danych obejmował ponad 460 punktów pomiarowych dla czynników R141b, R134a, R113, R123, R12, R11 i wody. Uzyskano...
-
Improved semi-empirical method for determination of heat transfer coefficient in flow boiling in conventional and small diameter tubes
PublicationPraca dotyczy przedstawienia poprawionego modelu umożliwiającego wyznaczanie współczynnika przejmowania ciepła w kanałach o małych średnicach jaj i tych tradycyjnych. Model zweryfikowano na 6 czynnikach chłodnuiczych uzyskując bardzo zadowalającą zgodność.
-
Direct Current Atmospheric Pressure Microdischarge Generated between a Miniature Flow Helium Microjet and a Flowing Liquid Cathode
Publication -
The Acute Effects of External Compression With Blood Flow Restriction on Maximal Strength and Strength-Endurance Performance of the Upper Limbs
Publication -
Best State Estimate for the Phase Angles of Busbars in Power Systems via Circuit Modeled with DC Load Flow
Publication -
A robust optimization model for affine/quadratic flow thinning: A traffic protection mechanism for networks with variable link capacity
Publication -
Investigation of the flow, heat and mass transfer and emissions in pulverized fuel fired boiler using physical and numerical modeling.
PublicationPraca przedstawia wykorzystanie techniki modelowania fizycznego trójwymiarowego oraz obliczeń numerycznych umożliwiających symulację rzeczywistych procesów spalania paliw stałych i gazowych w urządzeniach energetycznych. Dodatkowo wyniki obliczeń porównano z wynikami modelowania fizycznego oraz pomiarów na obiekcie rzeczywistym.
-
Nowy system diagnostyki cieplno-przepływowej obiektów energetycznych.The new system of power units thermal and flow diagnostics.
PublicationPrzedstawiono zmodernizowany system diagnostyki urządzeń składowych obiegów cieplnych bloków energetycznych. Wskazano na zalety zastosowania do tego sztucznych sieci neuronowych (SSN). Opisano dokładność SSN zastosowanych do poszukiwania typów degradacji geometrycznych i do rozpoznawania rozmiarów degradacji geometrycznych.
-
Badania wrzenia R22 w rurkach z powłoką porowatą. Investigation of R22 flow boiling in porous tubes.
PublicationW pracy przedstawiono wyniki pomiarów współczynnika przejmowania ciepła przy wrzeniu w przepływie R22 w poziomej rurce z aluminiową powłoką porowatą. Otrzymane dane odniesiono do wyników uzyskanych dla gładkiej stalowej rurki oraz rurki typu microfin. Rurka gładka i z powłoką porowatą była wykonana ze stali nierdzewnej o grubości ścianki 0.6 mm. Grubość powłoki porowatej wynosiła 0,2 mm. Eksperymenty prowadzono przy stopniu suchości...
-
Isolation of Human Progenitor Epidermal Cells on Collagen Type IV and Analysis of Their Markers with Flow Cytometry and PCR Methods
PublicationEpidermal stem cells, located in the skin, together with keratinocytes are transplanted in regenerative therapies, e.g., for the treatment of burns or other wounds. Here, we describe the protocol of their enzymatic isolation from human skin. It includes separation of the epidermis form the dermis by incubation with dispase followed by cell isolation for epidermis by digestion with trypsin. Cell isolated with this method can be...
-
Application of Particle Image Velocimetry method for monitoring the volume changes during silo flow on the basis of X-radiographs
PublicationW artykule przedstawiono wyniki badań nad zastosowaniem techniki pomiarowej PIV (Particle Image Velocimetry) do analizy zmian objętościowych zachodzących w materiale sypkim w czasie opróżniania silosu prostokątnego. Jako mateirły do analizy wykorzystano cyfrowe radiografy uzyskane z kontynualnej rejestracji z użyciem systemu tomografii promieni X. Szcególny nacisk położono na analizę zmian objętościowych zachodzącyh w kanale przepływu.