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Search results for: HEAT EXCHANGE IN HEAT RECOVERY STEAM GENERATORS (HRSG)
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Adapting the pinch point analysis to improve the ORC design process
PublicationPinch point analysis can be adapted so as to assist in the early stages of designing the ORC systems. Typically used in determining the working parameters of heat exchangers, it can be employed to improve the heat fitting between the source of heat and the working fluids of the ORC system. To attain the parametric match, an algorithm was built enabling quick estimation of the possible heat reception by the specific working fluid....
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FTIR-TiO2 heated at 400-600oC in Ar or H2
Open Research DataData contain FTIR diffuse eflectance spectra of TiO2, which was heat-treated at 400-600oC in Ar or H2. Hydrogen reduced TiO2 revealed new bands due to the adsorption of some species on the titania oxygen vacancy sites.
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Profitability criteria of partial cogeneration in nuclear power plant.
PublicationIn this paper, profitability criteria and calculation methodology of profitability conditions for partial cogeneration in nuclear power plant (NPP) was presented. Considered NPP supplies electricity to consumers through public power system, whereas heat is expected to be supplied to consumption regions via long-distance heat transport line. First proposed profitability criterion was total annual costs of electricity and heat delivered...
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Improved energy management technique in pipe-embedded wall heating/cooling system in residential buildings
PublicationEffective and environmentally responsive techniques of energy management in residential buildings are desirable for the resulting reduction of energy costs and consumption. In this paper, an improved and efficient technique of energy management in pipe-embedded wall heating/cooling systems, called the Thermal Barrier, is described. Specifically, the Thermal Barrier is a technique focused on the management and control of heat...
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Improved energy management technique in pipe-embedded wall heating/cooling system in residential buildings
PublicationEffective and environmentally responsive techniques of energy management in residential buildings are desirable for the resulting reduction of energy costs and consumption. In this paper, an improved and efficient technique of energy management in pipe-embedded wall heating/cooling systems, called the Thermal Barrier, is described. Specifically, the Thermal Barrier is a technique focused on the management and control of heat supply...
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Multicriteria Optimization Approach to Design and Operation of District Heating Supply System over its Life Cycle
PublicationDistrict Heating (DH) systems are commonly supplied using local heat sources. Nowadays, modern insulation materials allow for effective and economically viable heat transportation over long distances (over 20 km). In the paper a method for optimized selection of design and operating parameters of long distance Heat Transportation System (HTS) is proposed. The method allows for evaluation of feasibility and effectivity of heat transportation...
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Experimental investigation of domestic micro-CHP based on the gas boiler fitted with ORC module
PublicationThe results of investigations conducted on the prototype of vapour driven micro-CHP unit integrated with a gas boiler are presented. The system enables cogeneration of heat and electric energy to cover the energy demand of household. The idea of such system is to produce electricity for own demand or for selling it to the electric grid – in such situation the system user will became the prosumer. A typical commercial gas boiler,...
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Experimental investigation of domestic gas boiler fitted with ORC module
PublicationIn the paper the prototype of innovative domestic cogenerative ORC system, consisting of a conventional gas boiler and a small size axial vapour microturbines (in-house designed for ORC and the commercially available for Rankine cycle (RC)), evaporator and condenser were scrutinised. In the course of study the fluid working temperatures, rates of heat, electricity generation and efficiency of the whole system were obtained. The...
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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...
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Visualization of the surface of the Nafion membrane
Open Research DataFuel cells use the chemical energy of hydrogen or other fuels to produce electricity. If the fuel is hydrogen, the only products are electricity, water and heat. Fuel cells are unique in the variety of their potential applications, they can use a wide variety of fuels. They are also highly scalable devices that can power both cars and mobile phones....
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Bead-on-Plate Underwater Wet Welding on S700MC Steel
PublicationThe participation of high strength steels in marine and offshore structures is increasing, which makes it necessary to develop recommendations for underwater repair welding works. The article presents the results of bead-on-plate welded specimens made of S700MC high strength steel in underwater wet welding conditions by covered elec- trodes. Three specimens with heat input values in the range 0.91-1.05 kJ/mm were made. The specimens...
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Energy consumption optimization in wastewater treatment plants: Machine learning for monitoring incineration of sewage sludge
PublicationBiomass management in terms of energy consumption optimization has become a recent challenge for developed countries. Nevertheless, the multiplicity of materials and operating parameters controlling energy consumption in wastewater treatment plants necessitates the need for sophisticated well-organized disciplines in order to minimize energy consumption and dissipation. Sewage sludge (SS) disposal management is the key stage of...
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The structure of vanadate glass-ceramics containing BaTiO3 measured with X-ray diffraction method
Open Research DataThe structure of vanadate glass-ceramics doped with BaTiO3 was measured by XRD. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on a preheated...
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Photoluminescence spectra of TiO2
Open Research DataThese data contain photoluminescence spectra of TiO2 measured at the temperature of liquid nitrogen. There is a comparison of the photoluminescence spectra of TiO2 heat treated at 400-600oC in the ambient (Ar) and reduced (H2) atmospheres. These emission spectra were recorded after TiO2 excitation with a wavelength of 290 nm
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Flow boiling intensification in minichannels by means of mechanical flow turbulising inserts
PublicationThe work presents the results of experimental investigation on heat transfer in minichannels. Refrigerant R123 was used as a test fluid. Single vertical silver tubes of 380 mm length and 2.3 mm diameter were examined with two variants of turbulising inserts. A wide range of parameters was considered, namely mass flux G=534-3011 kg/(m2s), heat flux qw=28.5-68.4 kW/m2, saturation temperature Tsat=23-86 stC and the full range of vapour...
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Galerkin Finite Element Process for Entropy Production and Thermal Evaluation of Third-Grade Fluid Flow: A Thermal Case Study
Publication: A fluid’s moving class improves its heat transmission capability, as well as its rigidity, owing to multivariate molecule suspension. In this way, nanofluids are superior to common fluids. In this study, we evaluated the features of ease and heat transfer. Furthermore, we investigated permeable media, heat source, variable heat conductivity, and warm irradiation results. A mathematical technique known as the Galerkin finite element...
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Możliwości ograniczenia zużycia energii napędowej urządzeń przez optymalizację doboru wymienników ciepła, właściwą konfigurację i kontrolę przepływu płynów roboczych
PublicationArtykuł poświęcony możliwości ograniczenia zużycia energii napędowej urządzeń na drodze optymalizacji doboru wymienników ciepła, właściwej konfiguracji i kontroli przepływu płynów roboczych. Przedstawiono w nim ocenę zużycia energii w systemach energetycznych o największej energochłonności w realiach Polski. Zwrócono uwagę na możliwość wykorzystania wymienników ciepła o wysokiej efektywności dla zmniejszenia oporu przenoszenia...
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Approximation of Fractional Order Dynamic Systems Using Elman, GRU and LSTM Neural Networks
PublicationIn the paper, authors explore the possibility of using the recurrent neural networks (RNN) - Elman, GRU and LSTM - for an approximation of the solution of the fractional-orders differential equations. The RNN network parameters are estimated via optimisation with the second order L-BFGS algorithm. It is done based on data from four systems: simple first and second fractional order LTI systems, a system of fractional-order point...
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Carbon Dioxide Recovery Skid
PublicationIn the face of tightening climate regulations, the adoption of carbon dioxide recovery systems is inevitable. Modular process skid units have been widely adopted across the industry. The gas-steam power plant skid unit with the carbon dioxide recovery system was described. The proposed skid module consists of the compact cycle with the oxy-combustion and the carbon dioxide capture skid unit producing pure compressed CO2. The compactness...
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Performance of the domestic micro ORC equipped with the shell-and-tube condenser with minichannels
PublicationIn this paper, the original compact shell-and-tube heat exchanger with circular minichannels of in-house design and manufacturing is presented as the condenser for the domestic micro heat and power plant investigations as well as other future technical applications. The heat exchanger is equipped with turbulizing baffles inside the shell. The shell itself is made of a tubular sleeve having an inner diameter of 0.067 m and the length...
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Cooperation of ORC installation with a gas boiler as a perspective co-generation system for households
PublicationThis paper reports tests of an innovative micro-CHP unit prototype, consisting of a traditional gas boiler and organic Rankine cycle (ORC), which incorporates original system components such as an axial vapour microturbine, evaporator and condenser. The system co-generates heat and electricity for a single household or a group of households. Electricity is only a by-product during production of heat. While testing the prototype,...
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Experimental investigations on condensation in flow of HFE-7100 in small diameter channels
PublicationIn the paper the authors present investigations of flow condensation with the use of the HFE-7100 as a working fluid. The original and new approach to removing the heat from the channel was applied. The research was carried out using a wide-range real time observations, e.g. using infrared camera and stroboscope microphotography. This paper presents the details of experiment as well as the influence of heat and flow parameters...
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The Effect of Welding Conditions on Mechanical Properties of Superduplex Stainless Steel Welded Joints
PublicationThe tests results of superduplex stainless steel welded joints made with a different heat input, using automatic submerged arc welding (SAW) and semi-automatic flux-cored arc welding (FCAW) have been presented. Metallographic examinations, the measurements of the ferrite content, the width of the heat affected zone (HAZ) and the hardness of the welds in characteristic areas have been performed. Significant differences in the amount of...
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Numerical and experimental investigation of thermal convection near electric devices with vertical channels
PublicationThis paper presents the results of numerical and experimental investigation of thermal convection near heat emitting surfaces of an electric device. For the intensification of thermal convection, special vertical channels were formed near the heat emitting surfaces of the device. An experimental test has proved that there is an optimal length of the channels – thermal convection is the most intensive then. Air velocity vectors...
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The structure of strontium–borate glasses and glass-ceramics containing bismuth and vanadium oxides measured with X-ray diffraction method
Open Research DataThe structure of strontium–borate glasses and glass-ceramics containing bismuth and vanadium oxides was measured by XRD.
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Application of nanofluids in selected thermal technologies
PublicationSome peculiarities regarding convective heat transfer of nanofluids are presented. Particularly, results of the fundamental research concerning pool boiling and single phase convection of nanofluids as well as data obtained for selected heat exchangers operated with nanofluids are discussed.
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Energy Security of Polish Consumers in 2004-2021
Open Research DataEnergy security is one of the most important components of economic security. It is influenced not only by access to energy sources and the economic situation of the state and the individual consumer. In the years 2004–2021, energy security of the individual consumer in the economic dimension significantly improved. This was due to several factors:1....
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TG-hydroxyl groups in TiO2-P25
Open Research DataTG analyses were performed for powdered TiO2 - commercial P25 sample, which was heat-treated from room temperature to 500 C in the nitrogen atmosphere. Mass loss at lower temperature such as 120 C was related to the physisorbed water, and that one occurring at 500 C to the chemisorbed hydroxyl groups.
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Nanostructure and dielectric behavior of vanadate glasses containing BaTiO3
PublicationThe ac and dc electrical conductivity of barium titanate doped bismuth-vanadate as-quenched and heat-treated materials was measured in the frequency range from 1 mHz to 1 MHz and in the temperature range from 153 K to 423 K with the impedance spectroscopy method. The microstructure was investigated by means of XRD, scanning electron microscopy (SEM), atomic force microscopy (AFM) and confocal microscopy. The obtained results showed...
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SEM/EDX data of (Cr,Fe,Mn,Co,Ni)3O4 High-entropy spinel oxide thin films deposited on amorphous SiO2 substrate by spray pyrolysis techniqe
Open Research DataThis Data set include SEM and EDX results of (Mn,Co,Fe,Ni,Cr)3O4 high-entropy spinel oxide prepared in the form of a ~ 500 nm thin film utilising a facile spray pyrolysis technique. The structural and electrical properties of the layers were characterised after exposure to temperatures in the range of 400–900 ◦C. The as-deposited layers were amorphous,...
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TEM data of (Cr,Fe,Mn,Co,Ni)3O4 High-entropy spinel oxide thin films deposited on amorphous SiO2 substrate by spray pyrolysis techniqe
Open Research DataThis Dataset include presentation of summarized TEM investigation of (Mn,Co,Fe,Ni,Cr)3O4 high-entropy spinel oxide prepared in the form of a ~ 500 nm thin film utilising a facile spray pyrolysis technique. The structural and electrical properties of the layers were characterised after exposure to temperatures in the range of 400–900 ◦C. The as-deposited...
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Three phase transient model of wet coal pyrolysis
PublicationA one-dimensional transient mathematical model was developed to describe the thermal and flow phenomena during coal pyrolysis in a coke oven. The model was solved numerically using partly implicit methods for gas flow and heat transfer problems. It was successfully validated with industrial-scale measurements of temperature change in the middle-plane of the coke oven chamber. The evolution of temperature and pressure, distributions...
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Technical and Economic Analysis of the Supercritical Combined Gas-Steam Cycle
PublicationCombined cycle power plants are characterized by high efficiency, now exceeding 60%. The record-breaking power plant listed in the Guinness Book of World Records is the Nishi-Nagoya power plant commissioned in March 2018, located in Japan, and reaching the gross efficiency of 63.08%. Research and development centers, energy companies, and scientific institutions are taking various actions to increase this efficiency. Both the gas...
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EXPERIMENTAL INVESTIGATION OF FREE CONVECTION OF GLYCOL-Al2O3 NANOFLUID FROM HORIZONTAL TUBE
PublicationNanofluids came to be seen as a new generation of coolants, both in single- and two phase systems. Furthermore, nanofluids or nanocomposites may be used as a media in a thermal energy storage (TES) in such systems as sensible heat storage (SHS) and phase change materials (PCM). In the SHS systems the dominating mechanism of the heat transfer is natural convection. However, in the literature only a few investigations of free convection...
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Experimental investigation of forced convection of water-Al2O3 nanofluids inside horizontal tubes,
PublicationIn this paper, forced convection of water–Al2O3 nanofluids inside horizontal copper tube is studied experimentally. Experiments were conducted for three, i.e. 0.1%, 1% and 5% nanoparticle mass concentrations under transition and turbulent flow regimes. Average heat transfer coefficients and pressure drop values were determined and compared to distilled water. Enhancement of heat transfer for lower nanoparticle concentration and...
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Experimental investigation of free convection of glycol-Al2O3 nanofluid from horizontal tube
PublicationNanofluids came to be seen as a new generation of coolants, both in single- and two phase systems. Furthermore, nanofluids or nanocomposites may be used as a media in a thermal energy storage (TES) in such systems as sensible heat storage (SHS) and phase change materials (PCM). In the SHS systems the dominating mechanism of the heat transfer is natural convection. However, in the literature only a few investigations of free convection...
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MOŻLIWOŚĆ WYKORZYSTANIA ELEKTROWNI JĄDROWEJ JAKO ŹRÓDŁA ENERGII ELEKTRYCZNEJ I CIEPLNEJ
PublicationW niniejszym artykule przedstawiono zagadnienia związane z możliwością pracy elektrowni jądrowej (EJ) również w charakterze źródła ciepła, a więc w warunkach skojarzonego wytwarzania energii elektrycznej oraz ciepła. Rozpatrzono dwa poziomy mocy cieplnych oddawanych do systemów ciepłowniczych. Przeprowadzone wstępnie badania techniczne i ekonomiczne dla lokalizacji elektrowni jądrowej nad Jeziorem Żarnowieckim potwierdziły potencjalną...
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Bead-on-plate welding on S235JR steel by underwater local dry chamber process
PublicationThe article presents the results of the effect of parameters of underwater local dry chamber welding on the properties of padding welds. The effect of heat input and the type of shielding gas on the structure and hardness of welds was established. the functions for estimating the maximum hardness of the heat affected zone have been also elaborated.
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Testing an evaporator operation with a concave manifold, condenser temperature 30, evaporator temperature 70 and preheater temperature 60
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a bifurcation manifold, condenser temperature 20 and evaporator temperature 85
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a concave manifold, condenser temperature 30, evaporator temperature 70 and preheater temperature 40
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a trapezoidal manifold, condenser temperature 90 and evaporator temperature 90
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a bifurcation manifold, condenser temperature 20 and evaporator temperature 70
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a rectangular manifold, condenser temperature 30 and evaporator temperature 90
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a trapezoidal manifold, condenser temperature 70 and evaporator temperature 60
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a bifurcation manifold, condenser temperature 20 and evaporator temperature 95
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Testing an evaporator operation with a bifurcation manifold, condenser temperature 20 and evaporator temperature 90
Open Research DataThe experiment was conducted to test the evaporator operation. The heat exchanger was equipped with minigeometry (set of 50 parallel minichannels or single minigap). The studies were conducted for various mass flow rate of the working fluid and for various temperatures at the inlet of the evaporator. Accurate information about the test rig, the parameters...
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Wieloobszarowa rozmyta regulacja PID mocy reaktora jądrowego
PublicationW artykule przedstawiono wieloobszarowy regulator rozmyty z lokalnymi regulatorami PID dla sterowania mocą reaktora jądrowego typu PWR. Wykorzystano model matematyczny o parametrach skupionych reaktora PWR obejmujący procesy generacji i wymiany ciepła oraz efektów reaktywnościowych. Nastawy lokalnych regulatorów PID zostały dobrane w sposób optymalny, minimalizując całkowy wskaźnik jakości ISE. Na przykładzie pokazano że zastosowane...
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Phase Change Thermal Energy Storage – The Experience of the Materials Preparation for the Specific Applications.
PublicationThermal energy storage and temperature stabilization is very important in many engineering applications. There are three kinds of thermal energy storage: sensible heat storage, latent heat storage and reversible chemical reaction heat storage. Phase change materials (PCM) absorb, store and release large amounts of energy in the form of latent heat, at constant temperature, called the transition temperature. The amount of heat...
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The Effects of Pin Profile on HDPE Thermomechanical Phenomena during FSW
PublicationFriction stir welding (FSW) of polymeric materials has recently attracted significant attention. Herein, we present the effect of the tool pin profile on the FSW of high-density polyethylene (HDPE) joints through joint experimental analysis and thermomechanical simulations. For analysis of pin profile effects on the thermomechanical properties of HDPE joints, frustum (FPT), cubic (CPT), and triangular (TPT) pin shapes were selected...