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Natural radioactivity of solid and liquid phases from shale oil and gas prospection in Pomerania
PublicationIonizing radiation intensity data and estimation of equivalent absorbed dose from solid and liquid samples from prospection of shale gas and oil at selected sites in Pomerania are presented. Naturally occurring radioactive materials (NORM) are associated with geological formations or fluids and can be enhanced during oil and gas production. They appear in e.g. drilling cuttings, flow back water, produced water, scale and sludge....
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Optical emission spectroscopy of plasma generated by a waveguide-supplied microwave plasma source operated at 915MHz
PublicationIn this paper we present the results of an optical emission spectroscopic study of an atmospheric pressure microwave (915 MHz) nitrogen and nitrogen with carbon dioxide (1%) plasma at high working gas flow rate. This study was aimed at determining rotational Trot and vibrational Tvib temperatures of N+2 ions and N2, CN molecules. The plasma was generated in a waveguide-supplied cavity-resonant type microwave plasma source. All...
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Prediction of coking dynamics for wet coal charge
PublicationA one-dimensional transient mathematical model describing thermal and flow phenomena during coal coking in an oven chamber was studied in the paper. It also accounts for heat conduction in the ceramic oven wall when assuming a constant temperature at the heating channel side. The model was solved numerically using partly implicit methods for gas flow and heat transfer problems. The histories of temperature, gas evolution and internal...
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Investigation of Narrow Electrostatic Precipitator with Wire Multi-Electrode
PublicationDiesel engines emit fine particles, which are harmful to human and animal health. There are several methods for decrease particulate emission from a diesel engines, but up to now, these methods are notenough effective or very expensive. An electrostatic precipitation was proposed as an alternative method for control of a diesel particulate emission. Therefore, narrow electrostatic precipitators (ESPs) have become a subject of interest...
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The Influence of Water and Mineral Oil on Pressure Losses in Hydraulic Motor
PublicationIn this paper, pressure losses in hydraulic motor supplied with water and mineral oil (two liquids that have significantly different viscosity and lubricating properties) are described and compared. The experimental tests were conducted using a hydraulic satellite motor that is dedicated to working with different liquids, including water. The methodology of measuring the pressure drop in internal channels of this motor is also...
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Performance Evaluation of Selected Parallel Object Detection and Tracking Algorithms on an Embedded GPU Platform
PublicationPerformance evaluation of selected complex video processing algorithms, implemented on a parallel, embedded GPU platform Tegra X1, is presented. Three algorithms were chosen for evaluation: a GMM-based object detection algorithm, a particle filter tracking algorithm and an optical flow based algorithm devoted to people counting in a crowd flow. The choice of these algorithms was based on their computational complexity and parallel...
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Influence of mesh density on 2D viscous flutter in a turbomachinery cascade
PublicationIn this study numerical simulations of 2D viscous flutter were performed and compared with available experimental results for various mesh densities and flow parameters. Calculations were carried out for the bending oscillations of an Eleventh Standard Configuration cascade. ANSYS CFX code was used for the SST, SA and k-ω turbulence model calculations.
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VSC converters control for offshore wind farms HVDC grid connection
PublicationThe paper proposes a voltage sourced converter (VSC) new control method. A well-known in the electric power systems correlation between voltage angle and active power and correlation between voltage and reactive power is used instead of feedforward control. This allows for a fast and almost independent control of active and reactive power flow.
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Magnetic and capacitive couplings influence on power and energy measurement in double circuit high voltage overhead transmission line
PublicationThe paper discusses influence of magnetic and capacitive couplings on power and energy measurement in case of double circuit high voltage overhead transmission line. There are presented and discussed various factors influencing the power flow among the line‟s circuits. Mathematical model based calculations results are compared to the real transmission line measurements.
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Analysis of diagnostic informativeness of the exhaust temperature of a naval gas turbine
PublicationThe conducted investigations aimed to carry out an analysis of the possibility that the failures identification in the automatic control system of a gas turbine engine could be worked out on the basis of measurements of the exhaust stream temperature behind the gas generator. The exhaust temperature represents a basic control parameter, enabling technical state evaluation of the engine within the operation process, which is observed...
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Badania połączeń spawanych rurociągu wody pitnej we Włocławku, ang. Welding joints tests in drinking water pipeline.
PublicationCelem badań opisanych w pracy było określenie przyczyn korozji powstałej w strefie wpływu ciepła (SWC) w obwodowych połączeniach spawanych w rurociągu wody pitnej. Materiałem, z którego wykonano rurociąg to stal 304/304L. W obszarze złącza spawanego stwierdzono wżery inicjowane od niezgodności geometrycznych, gdzie mogły gromadzić się osady zwiększające udział chlorków bezpośrednio przy powierzchni rury, promujące tym procesy korozyjne....
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Evaluation of mercury content in combustible tobacco products by employing cold vapor atomic absorption spectroscopy and considering the moisture content: a comprehensive study
PublicationPlants are mainly made up of water, which constitutes between 80 and 90% of their weight. Moisture factor comes across as one of the most important in tobacco products. Rapid determination of moisture content in tobacco products comes at neces- sity in any tobacco management plants (before and after production). Therefore, the concern has been raised in this study to evaluate the moisture content in four kinds of combustible tobacco...
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Simulation of Residence Time Distribution and Mixing in Reactors with Recirculation Using 2D Approach
PublicationIn this paper, we propose a 2D approach in order to create a mathematical model for the determination of the residence time distribution for a flow reactor with recirculation. Apart from characterizing the functional residence time distribution, this model can help improve the operation of the reactor at the design stage. The mathematical model was validated by comparison with experiments carried out in a hydraulic laboratory.
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Wpływ liczby mieszkańców na obliczenia ilości ścieków w projektowaniu kanalizacji sanitarnej
PublicationZmiana sposobu rozliczania zużycia wody, promocja wodooszczędnych technologii oraz uszczelnienie kanałów wyraźnie wpłynęły na ilość odprowadzanych do kanalizacji ścieków. Obecnie stwierdzić można, że opracowania z lat 70-tych XX wieku podają zawyżone wskaźniki odpływu ścieków, skutkiem czego są problemy eksploatacyjne. Bez wątpienia, prawidłowe zaprojektowanie kanalizacji sanitarnej to zadanie trudne, wymagające między innymi prawidłowego...
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The novel sterilization device: the prototype testing
PublicationCurrently, there are numerous methods that can be used to neutralize pathogens (i.e., devices, tools, or protective clothing), but the sterilizing agent must be selected so that it does not damage or change the properties of the material to which it is applied. Dry sterilization with hydrogen peroxide gas (VHP) in combination with UV-C radiation is well described and effective method of sterilization. This paper presents the design,...
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The role of SSVF and SSHF beds in concentrated wastewater treatment, design recommendation
PublicationThe return flows of reject water from sewage sludge dewatering alter the activated sludge process ina conventional WWTP and increase TN concentration in the final effluent from WWTP. The objectiveof the investigation carried out was to consider the application of multistage treatment wetland(MTW) for the treatment of reject water from sewage sludge dewatering in a centrifuge (RWC). Thispaper aims to present the design and performance...
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New method to monitor changes in the subarachnoid width and pial artery pulsation for physiological and clinical research
PublicationThere are several medical conditions associated with brain oedema such as traumatic brain injury, intoxication or tumors. Brain edema and related brain parenchyma expansion may lead to compression and subsequent injury of several brain structures. So far, the only method enabling detection and monitoring of the progress a cerebral oedema in a patient, has been monitoring of intracranial pressure (ICP) with a pressure probe inserted...
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Multiobjective Aerodynamic Optimization by Variable-Fidelity Models and Response Surface Surrogates
PublicationA computationally efficient procedure for multiobjective design optimization with variable-fidelity models and response surface surrogates is presented. The proposed approach uses the multiobjective evolutionary algorithm that works with a fast surrogate model, obtained with kriging interpolation of the low-fidelity model data enhanced by space-mapping correction exploiting a few high-fidelity training points. The initial Pareto...
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Partial Admission Stages of High Efficiency for a Microturbine
PublicationThe paper presents the results of a design analysis of a micro-turbine for a co-generation micro-power plant working in accordance with organic Rankine cycle. The heat power of the plant is assumed equal to 20kW and the corresponding available electric output is estimated to be about 3kW. After the design analysis, the axial turbine with partial admission in all stages was built and tested experimentally. Special attention was...
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Partial Admission Stages of High Efficiency for a Microturbine
PublicationThe paper presents the results of a design analysis of a microturbine for a cogeneration micro-power plant working in accordance with organic Rankine cycle. The heat power of the plant is assumed equal to 20kW and the corresponding available electric output is estimated to be about 3 kW. After the design analysis, the axial turbine with partial admission in all stages was built and tested experimentally. Special attentionwas paid...
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On Accuracy Modeling of Gas Turbine Cycles by the In-house COM-GAS Code
PublicationIn this paper, a comparison of accuracy modeling of gas turbine cycles between the basic (classical) model and the in-house COM-GAS code has been presented. The basic model uses a semi-perfect gas and well known projecting assumption. On the other hand, the computational flow mechanics (CFM) basis on a real gas by using thermodynamic tables. The thermodynamic analysis of thermal cycles, simply gas cycle GT8C and gas turbine cycle...
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Modeling of low calorific gas burning in a deficient oxygen environment and high-temperature oxidizer
PublicationThe experimental research will be performed using the experimental facility with a combustion chamber. The oxygen concentration in combustion oxidizers will be varied from 21% by volume (normal) air to 2%. The test combustion chamber will be fed with propane or methane as the reference fuel, then with low calorific fuels as test gases obtained by mixing various combustible components, e.g. H2, CH4, CO, and neutral gases, e.g. N2,...
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Magnetoacoustic heating in a quasi-isentropic magnetic gas
PublicationThe nonlinear heating of a plasma which associates with the transfer of energy of magnetoacoustic waves into that of the entropy mode, is analytically studied. A plasma is uniform and motionless at equilibrium. Perturbations in a plasma are described by a system of ideal magnetohydrodynamic equations. The equilibrium straight magnetic strength and the wave vector form a constant angle which varies from 0 to π/2. There exist four...
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Heat transfer intensification by jet impingement – numerical analysis using RANS approach
PublicationJet impingement is a method of the heat transfer enhancement applied in the engineering systems. The idea is to generate fast-flow fluid jet which impinge on the heated (or cooled) surface, causing significantly higher heat transfer rate. Although some flat surface jet impingement cases are described in the literature, the validated data is still limited. The reason is coming from the fact, that these flows are hydrodynamically...
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Effects of FSW Tool Plunge Depth on Properties of an Al-Mg-Si Alloy T-Joint: Thermomechanical Modeling and Experimental Evaluation
PublicationOne of the main challenging issues in friction stir welding (FSW) of stiffened structures is maximizing skin and flange mixing. Among the various parameters in FSW that can affect the quality of mixing between skin and flange is tool plunge depth (TPD). In this research, the effects of TPD during FSW of an Al-Mg-Si alloy T-joint are investigated. The computational fluid dynamics (CFD) method can help understand TPD effects on FSW...
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Experimental and numerical study of thermal and electrical potential of BIPV/T collector in the form of air-cooled photovoltaic roof tile
PublicationAmong renewable energy sources, Building-Integrated Photovoltaic/Thermal (BIPV/T) systems are gaining increasing interest. To improve their economic competitiveness, technologies that increase their efficiency are searched for. The paper is devoted to evaluating the impact of various air-cooling configurations on the thermal and electrical performance of a photovoltaic roof tile. A numerical model of the own experimental system...
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Compact broadband multi-way 1:6 power divider
PublicationThis paper introduces a design flow of a microstrip multi-way 1:6 power divider incorporating photonic bandgap (PBG) structures. Themethod proposed has enabled the achievement of considerable miniaturization (15%) together with transmission characteristics enhancement(141% bandwidth). Measured results show significant similarity to theoretical characteristics, which proves the attractiveness of presented design methodology.
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Estimation of wind pressure acting on the new palm house in Gdansk
PublicationThis paper deals with the problem of numerical simulations of wind loads acting on a Palm House with complex geometry. Flow simulations with aid of computational fluid dynamics procedures have been performed to check if the pressure distributions for the structure are greater than those calculated using the standard design codes with assumption that the Palm House horizontal cross sections are described by smooth cylinders.
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Metoda diagnostyki cieplno-przepływowej turbin parowych wykorzystująca elementy algorytmów genetycznych
PublicationRozprawa doktorska poświęcona jest opisowi budowania metody diagnostyki cieplno-przepływowej z wykorzystaniem elementów algorytmów genetycznych. Do tworzenia założeń i algorytmów metody posłużono się przykładem funkcjonowania bloku elektrowni kondensacyjnej ze szczególnym uwzględnieniem układu łopatkowego turbiny parowej. Celem pracy jest zbudowanie metody diagnostyki cieplno-przepływowej. Zadaniem metody jest przeprowadzenie procesu...
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The protection and monitoring of a distribution piping network for potable water supply
PublicationPurpose – The purpose of this paper is to implement the corrosion protection method for steel pipes used in a municipal water-pipe network. Results of an inhibitor protection system installed on the system are presented. Inhibitor protection was required due to the high corrosivity of the water collected by a surface intake, which had resulted in a large number of failures and low water quality, due to the presence of corrosion...
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Thermal and Hydrodynamic Phenomena in the Stagnation Zone — Impact of the Inlet Turbulence Characteristics on the Numerical Analyses
PublicationOne of the methods of heat transfer enhancement is utilization of the turbulent impinging jets, which were recently applied, for example, in the heat exchangers. Their positive impact on the heat transfer performance was proven, but many questions related to the origin of this impact are still unanswered. In general, the wall-jet interaction and the near-wall turbulence are supposed to be its main reason, but their accurate numerical...
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Thermodynamic and economic analysis of nuclear power unit operating in partial cogeneration mode to produce electricity and district heat
PublicationThis paper presents the methodology of techno-economic analysis for a nuclear unit operating in partial cogeneration mode and its application for the case study: a nuclear power plant planned in Poland. The research objectives were: to propose EPR, AP1000 and ESBWR nuclear condensing-extraction turbine systems modifications required for operation in cogeneration, to determine optimal heat production and heat transport line (HTL)...
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CHARAKTERYSTYKA WYMIANY CIEPŁA I OPORÓW PRZEPŁYWU OMYWANIA MIKROSTRUGAMI ROZWINIĘTEJ POWIERZCHNI
PublicationW artykule przedstawiono eksperymentalne badania kompaktowego wymiennika ciepła z intensyfikacją przejmowania ciepła przy użyciu mikrostrug. Niniejszy artykuł przedstawia projekt i testy prototypu, wymiennika ciepła typu mikrostrugowego. Modułowa konstrukcja wymiennika umożliwia zmianę wymiarów geometrycznych, a także zmianę materiału przegrody wymiennika ciepła. Metoda graficzna Wilsona została z zastosowana w celu określenia...
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Methods of Determining Pressure Drop in Internal Channels of a Hydraulic Motor
PublicationIn this paper, new methods for determining the pressure drop in internal channels of a hydraulic motor are proposed and described. Mathematical models of pressure losses in internal channels have also been described. Experimental tests of the satellite motor were carried out according to one of the proposed methods. The tests were carried out for two liquids, i.e., water and mineral oil. Experimental studies have shown that at...
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New conjugates of tuftsin and muramyl dipeptide as stimulators of human monocytes-derived dendritic cells
PublicationMuramyl dipeptide (MDP) and tuftsin are known biologically active compound displaying a significant influence on various cell populations of innate immune response. MDP, as a fragment of bacterial cell wall, stimulates not only macrophages and monocytes, but also dendritic cells. In contrast, little is known about tuftsin influence on these cells. Therefore it seemed vital to access whether tuftsin or its derivatives conjugated...
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The impact of internal and international migration on regional convergence in Poland
PublicationAccording to neoclassical theory, migration is expected to speed up the convergence process between countries (Barro, Sala-i-Martin 2004). The flow of labour from low-wage regions to high-wage regions should equalise payrolls. However, the impact of migration on convergence rates is unclear when the labour flow is heterogeneous. Moreover, the movement of labour towards wealthier areas depresses the demand for goods, services and...
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Removal of cyclohexane and ethanol from air in biotrickling filters inoculated with Candida albicans and Candida subhashii
PublicationThis paper presents investigations on the removal of cyclohexane and ethanol from air in polyurethane- -packed biotrickling filters, inoculated with Candida albicans and Candida subhashii fungal species. Results on process performance together with flow cytometry analyses of the biofilm formed over packing elements are presented and discussed. The results indicate that the presence of ethanol enhances the removal efficiency of cyclohexane...
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DIGITAL HYDRAULICS CIRCUIT BASED ON PWM FUNCTION FOR CONTROLLING HYDRAULIC ACTUATOR POSITION
PublicationHydraulic systems are used in many different industries, such as multi-source hydrostatic drive systems. In traditional hydraulic systems, a proportional servo valve is used to control the position of hydraulic actuators. The low energy efficiency and high cost of these control valves are two major problems with these systems. Digital hydraulics is one of the most unique ideas on how to solve these problems. Researchers like digital...
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Numerical analysis of the ostiomeatal complex aeration using the CFD method
PublicationWe aimed to analyse ostiomeatal complex (OMC) aeration using the computational fluid dynamics (CFD) method of simulation based on human craniofacial computed tomography (CT) scans. The analysis was based on CT images of 2 patients: one with normal nose anatomy and one with nasal septal deviation (NSD). The Reynolds-Average Simulation approach and turbulence model based on linear eddy viscosity supplemented with the two-equation...
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Methodology of generation of CFD meshes and 4D shape reconstruction of coronary arteries from patient-specific dynamic CT
PublicationDue to the difficulties in retrieving both the time‑dependent shapes of the vessels and the generation of numerical meshes for such cases, most of the simulations of blood flow in the cardiac arteries use static geometry. The article describes a methodology for generating a sequence of time‑dependent 3D shapes based on images of different resolutions and qualities acquired from ECG‑gated coronary artery CT angiography. The precision...
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The influence of microjet array area ratio on heat transfer in the compact heat exchanger
PublicationThe paper describes the comprehensive study on the effect of microjet array geometrical parameters on the heat transfer enhancement in the modular heat exchanger. The conducted experimental study provides an experimental database on single phase submerged microjet heat transfer. The Wilson plot method was applied to determine the heat transfer coefficients in the laminar and transition flow regimes of a liquid-to-liquid heat exchanger....
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Numerical analysis of CO2-water separation in a horizontal double T-junction
PublicationCarbon dioxide is considered one of the main factors leading to global warming. Considering the significant impacts of CO2 on climate change, various technologies have been developed in recent decades to control carbon emission, such as for example CO2 capture and storage. The developed cycle of a negative CO2 emission power plant includes some devices, out of which, separator plays an indispensable role. To this end, T-junction...
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Research of hydrotronic variable displacement radial piston pump with electro -pneumatic control
PublicationThe paper presents the developed new electro-pneumatic control (pneumotronic) system for hydraulic fixed-displacement radial piston pump. Hydraulic fixed-displacement radial piston pump equipped with the proposed control system changes into hydrotronic variable-displacement radial piston pump. Pump flow rate control is realized by means of programmable logic controller, electro-pneumatic valves, pneumatic cylinders and a sensor.
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Research on protection mechanisms of Resilient Packet Ring Network.
PublicationPaper describes iSteering - a new method to control traffic in case of RPR network failure. There's comparison of packet wrapping, steering and our proposed method iSteering, which can be used in case of transmitter/receiver or fiber failure. Numerical analysis for even and random traffic flow has been made in order to compare packet wrapping, steering and iSteering. The results of all the tests are included.
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Systemy Smart Cities - studium przypadku
PublicationThe paper presents the architecture of an enterprise service bus used in the construction of information systems processing large amounts of data for decision-making needs at the City Hall in Gdańsk. The key concept of processes of bus development involves installation of developing environment, database connection, flow mechanisms and data presentation. The issue was supported by models such as KPI (Key Processes Identifier) and...
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A new model of fuel spray shape at early stage of injection in a marine Diesel engine
PublicationIn the cylinders of a marine diesel engine, self-ignition occurs in very shortly time after the fuel injection into the combustion chamber. Therefore, the paper present was to develop a model of diesel fuel spray for the early stage of fuel spray for in marine diesel engine. There were taken into consideration the main aspects technical such as nozzle diameter of marine engine injector and backpressure in combustion chamber. In...
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Sustainable recovery of plant essential Nitrogen and Phosphorus from human urine using industrial coal fly ash
PublicationCoal-based thermal power plants play a pivotal role in meeting global energy demand. The amount of fly ash generated from these plants increases every year, and its successful use has posed a significant environmental risk in the last decade. In this study, coal fly ash was packed in a fixed-bed adsorption column to remove Urea–N from synthetic human urine. To assess the efficacy of fly ash in the removal of Nitrogen, various process...
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Complex multidisciplinary optimization of turbine blading systems
PublicationThe paper describes the methods and results of direct optimization of turbine blading systems using a software package Opti_turb. The final shape of the blading is obtained from minimizing the objective function, which is the total energy loss of the stage, including the leaving energy. The current values of the objective function are found from 3D RANS computations (from a code FlowER) of geometries changed during the process...
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Analysis of cyclone separator solutions depending on SEC outlet conditions in nCO2PP
PublicationUtilization of spray ejector condenser in order to carry out direct-contact condensation of vapour with inert gas (CO2) on a spray of subcooled liquid integrated with separator (to make pure CO2) has been proposed for the task of condensation and CO2 separation in the negative CO2 emission gas power plant. Condensation and separation has a significant impact on the thermodynamic efficiency of the entire negative CO2 emission gas...
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The advanced monitoring as a key factor for appropriate optimization and control of full-scale activated sludge systems – case study Debogorze WWTP.
PublicationComputer simulation has become a helpful tool in wastewater treatment systems performance and effectiveness analysis. Advanced monitoring, by using appropriate software, enables to create a mathematical model of a real wastewater treatment plant (WWTP), run a simulation and subsequently interpret results under various conditions. An operation of WWTP is usually controlled by global parameters such as flow, solids retention time,...