Filters
total: 811
filtered: 789
-
Catalog
Chosen catalog filters
Search results for: FLOW PROCESS
-
Computational analysis of an infinite magneto-thermoelastic solid periodically dispersed with varying heat flow based on non-local Moore–Gibson–Thompson approach
PublicationIn this investigation, a computational analysis is conducted to study a magneto-thermoelastic problem for an isotropic perfectly conducting half-space medium. The medium is subjected to a periodic heat flow in the presence of a continuous longitude magnetic field. Based on Moore–Gibson–Thompson equation, a new generalized model has been investigated to address the considered problem. The introduced model can be formulated by combining...
-
Thermal Energy Development in Magnetohydrodynamic Flow Utilizing Titanium Dioxide, Copper Oxide and Aluminum Oxide Nanoparticles: Thermal Dispersion and Heat Generating Formularization
PublicationThe main aim of this article heat transfer in thermal engineering deals with the production, use, transformation, and transfer of thermal energy. Engineering and industrial fields including food packaging, the production of food additives, electronic cooling, microturbines, etc. heavily rely on heat transmission. Due to its intriguing potential in industries like the production of polymers, paper, crystal glass, etc., scientists...
-
Development of a spray-ejector condenser for the use in a negative CO2 emission gas power plant
PublicationOne promising solution for developing low-emission power technologies is using gaseous fuel combustion in pure oxygen when the exhaust gas mixture is composed of H2O and CO2, and where CO2 is separated after steam condensation. The paper presents the results of computational analyses providing to the Spray-Ejector Condenser (SEC) development, which is one of the crucial components of the negative CO2 gas power plant (nCO2PP) cycle...
-
Investigation of Mechanical and Microstructural Properties of Welded Specimens of AA6061-T6 Alloy with Friction Stir Welding and Parallel Friction Stir Welding Methods
PublicationThe present study investigates the effect of two parameters of process type and tool offset on tensile, microhardness, and microstructure properties of AA6061-T6 aluminum alloy joints. Three methods of Friction Stir Welding (FSW), Advancing Parallel-Friction Stir Welding (AP-FSW), and Retreating Parallel-Friction Stir Welding (RP-FSW) were used. In addition, four modes of 0.5, 1, 1.5, and 2 mm of tool offset were used in two welding...
-
Optimizing CO2 Purification in a Negative CO2 Emission Power Plant
PublicationIn the pursuit of mitigating CO2 emissions, this study investigates the optimisation of CO2 purification within a Negative CO2 Emission Power Plant using a spray ejector condenser (SEC) coupled with a separator. The approach involves direct-contact condensation of vapour, primarily composed of an inert gas (CO2), facilitated by a subcooled liquid spray. A comprehensive analysis is presented, employing a numerical model to simulate...
-
Direct-contact condensation from vapour- gas mixture in a spray ejector condenser for negative CO2 power plant
PublicationDirect-contact condensation of vapour containing the inert gas on a spray of subcooled liquid exists in a number of technical applications. For example, it may be found in the nuclear industry (e.g. pressurized jet under normal operating conditions, in safety analyses) or in the chemical industry (e.g. mixing-type heat exchanger, degasser, sea water desalting). The problem is also essential to modelling and analysis of some...
-
Pathways of nitrogen compounds depletion in hybrid constructed wetlands
PublicationHybrid Constructed Wetlands are composed of two or more filters with mixed flow direction of sewage. Apparently in the HCWS the benefits of both types of bed are merged, resulting in better effluent quality (organic and nitrogen componds removal). Such heterogeneous environment creates possibilities for different ways of nitrogen "disappearing". The objective of the present study was to compare the removal of nitrogen with accompanying...
-
Effect of nitrogen doping on TiOxNy thin film formation at reactive high-power pulsed magnetron sputtering
PublicationThe paper is focused on a study of formation of TiOxNy thin films prepared by pulsed magnetron sputtering of metallic Ti target. Oxygen and nitrogen were delivered into the discharge in the form of reactive gases O2 and N2. The films were deposited by high-power impulse magnetron sputtering working with discharge repetition frequency f = 250 Hz at low (p = 0.75 Pa) and high (p = 10 Pa) pressure. The substrates were on floating...
-
Application of Vertical Reed Beds as a Buffer for Effluent from SBR ANAMMOX Treatment for Reject Water from Centrifugation
PublicationThe main purpose of this study is to determine the removal efficiency of nitrogen compounds in the effluentfrom ANAMMOX process used to treat reject water after centrifugation. A pilot model was bulit consisting of fourdifferent Treatment Wetlands beds with different filter substrate and with or without macrophytes growth. Verticalsubsurface flow type filters have been choosen thanks to their highest efficiency in NH4-N removal...
-
Modelling of FloodWave Propagation with Wet-dry Front by One-dimensional Diffusive Wave Equation
PublicationA full dynamic model in the form of the shallow water equations (SWE) is often useful for reproducing the unsteady flow in open channels, as well as over a floodplain. However, most of the numerical algorithms applied to the solution of the SWE fail when flood wave propagation over an initially dry area is simulated. The main problems are related to the very small or negative values of water depths occurring in the vicinity of...
-
Application of an Electronic Nose Instrument to Fast Classification of Polish Honey Types
PublicationThe paper presents practical utilization of an electronic nose prototype, based on the FIGARO semiconductor sensors, in fast classification of Polish honey types—acacia flower, linden flower, rape, buckwheat and honeydew ones. A set of thermostating modules of the prototype provided gradient temperature characteristics of barbotage-prepared gas mixtures and stable measurement conditions. Three chemometric data analysis methods...
-
Rearrangements of the nitrifiers population in an activated sludge system under decreasing solids retention times
PublicationDue to the key role of nitrite in novel nitrogen removal systems, nitrite oxidizing bacteria (NOB) have been receiving increasing attention. In this study, the coexistence and interactions of nitrifying bacteria were explored at decreasing solids retention times (SRTs). Four 5-week washout experiments were carried out in laboratory-scale (V=10 L) sequencing batch reactors (SBRs) with mixed liquor from two full-scale activated sludge...
-
Predicting Ice Phenomena in a River Using the Artificial Neural Network and Extreme Gradient Boosting
PublicationForecasting ice phenomena in river systems is of great importance because these phenomena are a fundamental part of the hydrological regime. Due to the stochasticity of ice phenomena, their prediction is a difficult process, especially when data sets are sparse or incomplete. In this study, two machine learning models—Multilayer Perceptron Neural Network (MLPNN) and Extreme Gradient Boosting (XGBoost)—were developed to predict...
-
MEMS Technology Quality Requirements as Applied to Multibeam Echosounder
PublicationSmall, lightweight, power-efficient, and low-cost microelectromechanical system (MEMS) inertial sensors and microcontrollers, available in the market today, help reduce the instability of Multibeam Sonars. Current MEMS inertial measurement units (IMUs) come in many shapes, sizes, and costs — depending on the application and performance required. Although MEMS inertial sensors offer affordable, appropriately scaled units, they are...
-
Dynamic model of nuclear power plant turbine
PublicationThe paper presents the dynamic multivariable model of Nuclear Power Plant steam turbine. Nature of the processes occurring in a steam turbine causes a task of modeling it very difficult, especially when this model is intended to be used for on-line optimal process control (model based) over wide range of operating conditions caused by changing power demand. Particular property of developed model is that it enables calculations...
-
Nitrogen mass balance and mathematical model of a Structured- Bed Reactor (SBRRIA)
PublicationAn up-flow structured-bed reactor subjected to recirculation and intermittent aeration (SBRRIA) was operated under varying influent conditions. The influent COD/N ratio was adjusted by maintaining a stable organic loading rate (average of 1.07 kgCOD m-3 d-1) and changing the nitrogen loading rate from 0.1 to 0.4 kg N m-3. Therefore, three different COD/N ratios were tested: 9.7±1 (Scenario 1); 7.6±1 (Scenario 2) and 2.9±1 (Scenario...
-
Numeryczne modelowanie prędkości płynięcia warstw blachy bimetalowej w procesie walcowania = The numerical modelling of the layers flow velocity in bimetal plates rolling proces
PublicationW pracy przedstawiono wyniki obliczeń numerycznych dotyczących procesu asymetrycznego walcowania blach bimetalowych 18G2A+1H13.
-
Cardiovascular and Perceptual Responses to Resistance Training with Practical Blood Flow Restriction Induced by a Non-Elastic Band vs. Pneumatic Cuff: A Crossover Randomized Study
Publication -
Wyznaczanie współczynnika przejmowania ciepła podczas wrzenia w przepływie dwutlenku węgla (Prediction of flow boling heat transfer coefficient for carbon dioxide in minichannels)
PublicationW pracy przedstawiono wyniki obliczeń uzyskane za pomocą własnego modelu półemirycznego dla wybranych danych eksperymentalnych dla wrzenia w przepływie dwutlenku węgla. Metoda obliczeniowa została zweryfikowana z danymi eksperymentalnymi Docoulombiera i innych (2011) oraz Mastrullo i innych (2009). Badania eksperymentalne dotyczą pełnego zakresu zmienności stopnia suchości oraz zakresu prędkości masowej G=200-1200 kg/m2s. rozwijany...
-
Aiding (opponent) flow of hybrid copper–aluminum oxide nanofluid towards an exponentially extending (lessening) sheet with thermal radiation and heat source (sink) impact
Publication -
MHD darcy-forchheimer nanofluid flow and entropy optimization in an odd-shaped enclosure filled with a (MWCNT-Fe3O4/water) using galerkin finite element analysis
Publication -
Some coatings of high cavitation resistance produced by CO2 laser beam. XIV International Symposium on Gas Flow, Chemical Lasers and High Power Lasers.
PublicationPrzedstawiono wyniki badań odporności kawitacyjnej stali 2H13, 45 i żelaza Armco po laserowym stopowaniu ich powierzchni różnymi kompozycjami proszków Co, Mo, Ni, Mn i Cr, Ti. Wykazano różne własności kawitacyjne otrzymanych warstw w zależności od otrzymanej mikrostruktury.
-
A device for measuring heat flux on a rocket skin surface
PublicationA novel method for measuring heat flux on a surface is presented. It is an extensive upgrade of currently known heat flux sensors used mostly in civil engineering. As the thermal environment of launchers, especially sounding rocket can have an enormous negative effect on payload, careful considerations have to be taken in the process of preparing insulation. Usually, thermal data provided by the launch vehicle manufacturer is limited...
-
The Processing Procedure for the Interpretation of Microseismic Signal Acquired from a Surface Array During Hydraulic Fracturing in Pomerania Region in Poland
PublicationHydraulic fracturing is a procedure of injecting high pressure fluid into the wellbore in order to break shell rock and facilitate gas flow. It is a very costly procedure and, if not conducted properly, it may lead to environmental pollution. To avoid costs associated with pumping fluid outside the perspective (gas rich) zone and improve one’s knowledge about the reservoir rock, microseismic monitoring can be applied. The method...
-
REVERSE MODELLING OF MICROSEISMIC WAVES PROPAGATION FOR THE INTERPRETATION OF THE DATA FROM HYDRAULIC FRACTURING MONITORING IN POLAND
PublicationA hydraulic fracturing job was performed to stimulate gas flow from a horizontal wellbore located in Poland. The whole operation was overseen by means of microseismic monitoring. For this purpose, an array of 12000 geophones was deployed on ground in form of patches distributed unevenly in a region of 4km from the wellbore. The array was constantly recording seismic signals during whole fracturing processed. Such recorded signals...
-
Evaluation of the significance of the effect of the active cross-sectional area of the inlet air channel on the specific enthalpy of the exhaust gas of a diesel engine using statistics F of the Fisher-Snedecor distribution
PublicationThis paper presents the application of Fisher-Snedecor distribution F statistics to assess the significance of the influence of changes in the active cross-sectional area of the inlet air channel (Adol) flow in a diesel engine on the observed diagnostic parameter determined on the basis of measurements of the quick changing exhaust gas temperature in the outlet channel, which is the specific enthalpy of the exhaust gas stream within...
-
Transformational leadership for researcher’s innovativeness in the context of tacit knowledge and change adaptability
PublicationThis study explores how a learning culture supported by transformational leadership influences tacit knowledge sharing and change adaptability in higher education and how these relations impact this sector’s internal and external innovativeness. The empirical model was tested on a sample of 368 Polish scientific staff using the structural equation modeling (SEM) method. Then results were expanded by applying OLS regression using...
-
Impact of rotor geometry optimization on the off-design ORC turbine performance
PublicationThe paper describes the method of CFD based Nelder-Mead optimization of a 10 kW single-stage axial turbine operating in an ORC system working on R7100. The total-to-static isentropic efficiency is defined as an objective function. Multi-point linear regression is carried out to determine the significance of the objective function arguments and to pick up the set of particular variables and characteristic quantities (e.g. flow angles)...
-
Injectable poloxamer/graphene oxide hydrogels with well‐controlled mechanical and rheological properties
PublicationAlthough significant progress has been made in the design and application of injectable hydrogels for biomedical applications, concurrent control of rheological and mechanical properties of injectable hydrogels has remained as an open challenge to the researchers. In this work, we introduce and put into practice a photo‐curable poloxamer (also known as Pluronic)/graphene oxide (Plu/GO) injectable hydrogel with well‐controlled rheological...
-
Freeze-Up Ice Jam Formation in the River Bend, a Case Study on the Inner Mongolia Reach of Yellow River
PublicationConcern has been expressed regarding the impacts of climate change on river ice and ice jam formation in cold regions. Ice jams are easily initiated in bends and narrow channels and cause disasters. In this study, observations and remote sensing monitoring are used to study the freeze-up ice jam formation of bends. Sediment transport and freezing process of the river interact, influencing bed changes profile and sedimentary budget....
-
Comparison of the performance of direct current atmospheric pressure glow microdischarges operated between a small sized flowing liquid cathode and miniature argon or helium flow microjets
Publication -
Coupled Urban Areas Inundation Model with Interaction Between Storm Water System and Surface Flow - Case Study of Sea Level Impact on Seaside Areas Flooding
PublicationInundations are becoming more frequent than ever. What is connected with increasing area of impervious surface in cities. This makes predicting urban flooding and its scale especially important. At the seaside we observe additional conditions such as sea level that makes accurate numerical modelling of issue even harder. With complex approach to the matter which is simultaneous calculation of storm water conduit flow and overland...
-
Numeryczna analiza trójwymiarowego przepływu w polimerowym łożysku smarowanym wodą = Numerical analysis of three dimensional flow in water lubricated bearing with polymer bearing bush
PublicationW referacie przedstawiono wyniki obliczeń łożysk smarowanych wodą w oparciu o metodę CFD - obliczeniowej mechaniki płynów. Wykazano przydatność nowoczesnych narzędzi obliczeniowych do rozwiązywania podobnych problemów.
-
Przepływ wody w ośrodkach nienasyconych o podwójnej porowatości: zastosowanie metody homogenizacji. Unsaturated water flow in double porosity media: application of the homogenization theory
PublicationPrzedstawiono model matematyczny przepływu w gruncie o podwójnej porowatości wyprowadzony metodą homogenizacji. Otrzymano równanie makroskopowe z parametrami efektywnymi i członem źródłowym. Przedstawiono wyniki przykładowych obliczeń numerycznych i porównania z modelem znanym z literatury.
-
Comparative study of a bottoming SRC and ORC for Joule–Brayton cycle cooling modular HTR exergy losses, fluid-flow machinery main dimensions, and partial loads
PublicationEnergy conversion efficiency increase in power plants with high-temperature gas-cooled reactors via implementation of the bottoming cycle was investigated under nominal and minimal thermal load of a high-temperature reactor (HTR). Heat transfer surface area and turbine outlet volumetric flow rate in bottoming cycles was also investigated. Water and two low-boiling point working fluids (ammonia and ethanol) were analyzed. Analyzed...
-
A significance of multi slip condition for inclined MHD nano-fluid flow with non linear thermal radiations, Dufuor and Sorrot, and chemically reactive bio-convection effect
PublicationThe aim of this research is to discuss the significance of slip conditions for magnetized nanofluid flow with the impact of nonlinear thermal radiations, activation energy, inclined MHD, sorrot and dufour, and gyrotactic micro motile organisms over continuous stretching of a two-dimensional sheet. The governing equations emerge in the form of partial differential equations. Since the resultant governing differential equations...
-
Application of the F-statistic of the Fisher-Snedecor distribution to analyze the significance of the effect of changes in the compression ratio of a diesel engine on the value of the specific enthalpy of the exhaust gas flow
PublicationThe paper discusses the impact of changes in the compression ratio on the operating parameters of a diesel engine, e.g. on the temperature of exhaust gases. It presents the construction of the laboratory test stand, on which experimental measurements were realized. It is characterized how the actual changes of the compression ratio were introduced to the existing engine. The program of experimental investigations taking into account...
-
Koncepcja logistycznego usprawnienia magazynu cross-dockowego przedsiębiorstwa X
PublicationCelem artykułu jest przedstawienie koncepcji logistycznego usprawnienia magazynu cross- -dockowego przedsiębiorstwa X. W oparciu o informacje dotyczące stanu faktycznego maga- zynu zostały przeprowadzone badania procesów magazynowych. Po przeprowadzeniu identyfikacji problemów zostały zaproponowane usprawnienia wybranego procesu magazynowego, które polegały na propozycji zmiany sposobu zagospodarowania magazynu. Do tego...
-
Prediction of energy consumption and evaluation of affecting factors in a full-scale WWTP using a machine learning approach
PublicationTreatment of municipal wastewater to meet the stringent effluent quality standards is an energy-intensive process and the main contributor to the costs of wastewater treatment plants (WWTPs). Analysis and prediction of energy consumption (EC) are essential in designing and operating sustainable energy-saving WWTPs. In this study, the effect of wastewater, hydraulic, and climate-based parameters on the daily consumption of EC by...
-
Reservoir Influence on Pressure Wave Propagation in Steel Pipes
PublicationThe relation between the length of steel pipe and the pressure wave period in the system, reservoir-pipe-valve, is discussed. Experiments carried out for the short steel pipes showed that in such a system, the pressure wave celerity estimated using the measured wave cycles systematically increases with the increase of the pipe length. The observed differences can exceed even 90 m=s. As the pressure wave traveling in the pipe with...
-
Development of the System Assurance Reference Model for Generating Modular Assurance Cases
PublicationAssurance cases are structured arguments used to demonstrate specific system properties such as safety or security. They are used in many industrial sectors including automotive, aviation and medical devices. Larger assurance cases are usually divided into modules to manage the complexity and distribute the work. Each of the modules is developed to address specific goals allocated to the specific objects i.e. components of the...
-
A comparative analysis of methods and tools for low impact development (LID) site selection
PublicationThe site selection for Low Impact Development (LID) practices is a significant process. It affects the effectiveness of LID in controlling stormwater surface runoff, volume, flow rate, and infiltration. This research paper presents a comprehensive review of various methods used for LID site selection. It starts by introducing different methods and tools. Three main methods: index-based methods, GIS-based multi-criteria decision...
-
Identification of Parameters Influencing the Accuracy of the Solution of the Nonlinear Muskingum Equation
PublicationTwo nonlinear versions of the Muskingum equation are considered. The difference between both equations relates to the exponent parameter. In the first version, commonly used in hydrology, this parameter is considered as free, while in the second version, it takes a value resulting from the kinematic wave theory. Consequently, the first version of the equation is dimensionally inconsistent, whereas the proposed second one is consistent. It...
-
The role of hydrogen bonding on tuning hard-soft segments in bio-based thermoplastic poly(ether-urethane)s
PublicationThis work describes the preparation of bio-based thermoplastic poly(ether-urethane)s (TPU) via a prepolymer method and investigates the effect of varying the interphase hydrogen-bonding (H-bonding) on physicochemical, thermal and mechanical properties. This was achieved by varying the glycol type and molar ratio of [NCO]/[OH] groups used during the prepolymer chain extending step. The TPUs’ chemical structure was analyzed by Fourier...
-
Indoor accelerated controlled corrosion degradation test of small- and large-scale specimens
PublicationThe work presented here is a part of a long-term project analysing the structural behaviour of ageing marine structures. An accelerated corrosion degradation set-up was developed to reproduce corroded marine structural specimens of different degrees of degradation, controlling various natural factors, i.e., temperature, oxygen content, salinity, and flow velocity. The nine stiffened plates of 1.2 m length and 30 small scale specimens...
-
Two-dimensional vertical Reynolds-averaged naviers-stokes equations versus one-dimensional Saint-Venant model for rapidly varied open channel water flow modelling
PublicationPrzedstawiono dwa modele przepływu wody ze swobodną powierzchnią -płaski pionowy model Reynoldsa i model de Saint-Venanta.Do rozwiązania równań pierwszego modelu zastosowano schemat SIMPLE oraz wykorzystano metodę cząstek znaczonych MAC do wyznaczania swobodnej powierzchni wody. Równania Saint-Venanta rozwiązano metodą objętości skończonych. Obydwa modele zastosowano do symulacj zjawiska typu katastrofa zapory. Porównano wyniki...
-
Second law analysis of a 3D magnetic buoyancy-driven flow of hybrid nanofluid inside a wavy cubical cavity partially filled with porous layer and non-Newtonian layer
Publication -
Reliability of nitrogen removal processes in multistage treatment wetlands receiving high-strength wastewater
Publicationreatment wetlands have been proved to be more effective than conventional treatment processes in case of high-strength wastewater containing high concentrations of ammonium nitrogen and recalcitrant organic matter. In this study nitrogen removal processes and reliability of nitrogen removal at two identical pilot-scale multistage treatment wetlands (MTWs) receiving real, non-synthetic wastewater were discussed. The wastewater discharged...
-
In vitro biological evaluation of a novel folic acid-targeted receptor quantum dot−β−cyclodextrin carrier for C-2028 unsymmetrical bisacridine in the treatment of human lung and prostate cancers
PublicationTraditional small-molecule chemotherapeutics usually do not distinguish tumors from healthy tissues. However, nanotechnology creates nanocarriers that selectively deliver drugs to their site of action. This work is the next step in the development of the quantum dot−β−cyclodextrin−folic acid (QD−β−CD−FA) platform for targeted and selected delivery of C−2028 unsymmetrical bisacridine in cancer therapy.Herein, we report an initial...
-
Towards a Universal Model of Engineering Change Management
PublicationThe paper deals with the issue of engineering change management (ECM). ECM has received much less attention in the literature than general change management. Moreover, due to their specifics (complexity and multifaceted nature), hitherto developed ECM models are difficult to implement in companies. The paper aims to develop a simplified, universal, and hence easily applicable model of ECM. We based our assumptions on a case study...