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Search results for: FIRST-PRINCIPLES CALCULATIONS
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Euilibrium composition of CH4-CO2-CO-H2-H2O system for CO2/H2/H2O methanation
Open Research DataThe equilibrium compositions of CH4, CO2, CO, H2, H2O without C under the methanation reaction of 1:2 CO:H2 syngas mixtures were supplied with this dataset
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Synthesis, structural characterization and reactivity of new trisubstituted N1-acylamidrazones: solid state and solution studies
PublicationA series of new linear trisubstituted N1-acylamidrazones have been investigated using a variety of analytical techniques and theoretical calculations to check the influence of the type of N1-acyl substituent on the resonance forms and conformational behavior in the solid state and in solution. The 1D- and 2D-NMR experiments, supported by computational studies, revealed that in solution all amidrazones exhibit conformational syn/anti...
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Organic Supercritical Thermodynamic Cycles with Isothermal Turbine
PublicationOrganic Rankine cycles (ORC) are quite popular, but the overall efficiencies of these plants are rather very low. Numerous studies have been conducted in many scientific centers and research centers to improve the efficiency of such cycles. The research concerns both the modification of the cycle and the increase in the parameters of the medium at the inlet to the turbine. However, the efficiency of even these modified cycles rarely...
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A LUMPED-CIRCUIT MODEL OF CIRCULAR PISTON TRANSDUCER FOR MODELING ITS PERFORMANCE IN DUAL FREQUENCY OPERATING MODES
PublicationThe paper presents novel network equivalent circuit of piezoceramic circular disc transducer that takes into account thickness and ra dial mode of vibrations. The starting point of the analysis is 4-port description of circular disc element representing the solution of wave equation set in radial and thickness directions. Th e approximate solution for harmonic case is represented in the form of 4x4 matrix, which is syn thesized...
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Flow Process Models for Pipeline Diagnosis
PublicationThis chapter examines the problem of modeling and parameterization of the transmission pipeline flow process. First, the base model for discrete time is presented, which is a reference for other developed models. Then, the diagonal approximation (AMDA) method is proposed, in which the tridiagonal sub-matrices of the recombination matrix are approximated by their diagonal counterparts, which allows for a simple determination of...
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The Development of a Combined Method to Quickly Assess Ship Speed and Fuel Consumption at Different Powertrain Load and Sea Conditions
PublicationDecision support systems (DSS) recently have been increasingly in use during ships operation. They require realistic input data regarding different aspects of navigation. To address the optimal weather routing of a ship, which is one of the most promising field of DSS application, it is necessary to accurately predict an actually attainable speed of a ship and corresponding fuel consumption at given loading conditions and predicted...
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The Selection of Anchoring System for Floating Houses by Means of AHP Method
PublicationThis paper indicates and analyses the use of anchoring systems, such as mooring piles, booms, mooring cables, and deadweight anchors with additional elastic connectors, which are the most frequently applied by the producers of floating houses. The selection of the most advantageous anchoring system is complicated and requires the application of quantitative and qualitative data and methods. This publication presents the results...
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FE investigations of the effect of fluctuating local tensile strength on coupled energetic-statistical size effect in concrete beams
PublicationThe effect of fluctuating local tensile strength on a coupled energetic-statistical size effect in plain concrete beams under bending was numerically investigated. First, the influence of varying autocorrelation length of the random field describing a spatial variation of local tensile strength was studied. Next, the influence of the coefficient of variation of local tensile strength was analyzed. The numerical FE investigations...
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A tetragonal polymorph of SrMn2P2 made under high pressure – theory and experiment in harmony
PublicationFollowing the predictions of total energy calculations, a tetragonal SrMn2P2 phase is proposed and successfully formed under high pressure. At ambient pressure, SrMn2P2 adopts the primitive trigonal La2O3 structure type (space group P[3 with combining macron]m1). However, the results of total energy calculations indicate that SrMn2P2 should be more stable in the tetragonal ThCr2Si2 structure type (space group I4/mmm) than in its...
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Prediction of flow boiling heat transfer coefficient for carbon dioxide in minichannels and conventional channels
PublicationIn the paper presented are the results of calculations using authors own model to predict heat transfer coefficient during flow boiling of carbon dioxide. The experimental data from various resea rches were collected. Calculations were conducted for a full range of quality variation and a wide range of mass velocity. The aim of the study was to test the sensitivity of the in-house model. The results show the importance of taking into...
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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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22/23_winter_ Legislative technique in planning
e-Learning CoursesThe objective of the module is for students to understand the principles of legislative technique and to be able to apply them correctly in the planning documents they draw up.
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23/24_winter_ Legislative technique in planning
e-Learning CoursesThe objective of the module is for students to understand the principles of legislative technique and to be able to apply them correctly in the planning documents they draw up.
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Low-energy positron scattering from gas-phase pyrimidine: A quantum treatment of the dynamics and a comparison with experiments
PublicationWe are reporting detailed quantum scattering calculations that describe the diffusion of a beam of low-energy positrons interacting with the pyrimidine target as a gas-phase partner. The calculations have employed an essentially ab initio model for the short-range correlation interaction and for the electrostatic interaction of an impinging positron and the electron+nuclear structure of the target molecule at its equilibrium geometry.
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EXPERIMENTAL VERIFICATION OF THE METHOD OF FLOW BOILING AND FLOW CONDENSATION HEAT TRANSFER PREDICTION FOR SELECTED FLUIDS
PublicationIn the paper presented are the results of calculations using authors own model to predict heat transfer coefficient during flow boiling of different refrigerants. The experimental data from various research studies from literature were collected. Calculations were conducted for a full range of quality variation and a wide range of mass velocity. The aim of the study was to test the sensitivity of the in- house developed model....
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Geotechnics
e-Learning CoursesThe course is divided into two parts. The first is related to in-situ tests and their applications for the design of shallow and deep foundations. The second part is related to models of soil behavior and numerical analysis in geotechnical engineering.
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Euilibrium composition of CH4-CO2-CO-H2-H2O-C system under various compositions syngas methanation with 10% water vapour introduced
Open Research DataThe equilibrium compositions of CH4, CO2, CO, H2, H2O and C under the methanation reaction of various syngas mixtures (different CO/H2 ratio) were supplied with this dataset
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Euilibrium composition of CH4-CO2-CO-H2-H2O-C system under various compositions syngas methanation with 30vol.% water vapour introduced
Open Research DataThe equilibrium compositions of CH4, CO2, CO, H2, H2O and C under the methanation reaction of various syngas mixtures (different CO/H2 ratio) were supplied with this dataset
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Hydropower potential of the lower Vistula
PublicationThis paper presents an estimate analysis of the hydropower potential of the lower Vistula River from Warsaw to Gdańsk Bay. The calculations were made for a hydraulic model of the lower Vistula which takes into account potential development of barrages in a cascade system. Results obtained from the model simulations and from hydrological calculations were used to estimate the power of hydropower plants and the average annual energy...
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Pumps, Turbines and Small Hydropower, LEC/LAB, DaPE, sem.5 winter 2022/23 (M:320403W0)
e-Learning CoursesThe aim of the course is to identify and demonstrate knowledge of the major concepts, theoretical perspectives, and historical trends in small hydropower. This course examines the principles of sustainability and renewable energy conversion with emphasis on hydro energy resources. Concentration is placed on the relationships between the renewable resources, conversion technology and economic feasibility along with consideration...
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Pumps, Turbines and Small Hydropower, LEC/LAB, ET, sem.7 winter 2022/23 (PG_00042108)
e-Learning CoursesThe aim of the course is to identify and demonstrate knowledge of the major concepts, theoretical perspectives, and historical trends in small hydropower. This course examines the principles of sustainability and renewable energy conversion with emphasis on hydro energy resources. Concentration is placed on the relationships between the renewable resources, conversion technology and economic feasibility along with consideration...
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Pumps, Turbines and Small Hydropower, LEC/LAB, DaPE, sem.5 winter 2023/24 (M:320403W0)
e-Learning CoursesThe aim of the course is to identify and demonstrate knowledge of the major concepts, theoretical perspectives, and historical trends in small hydropower. This course examines the principles of sustainability and renewable energy conversion with emphasis on hydro energy resources. Concentration is placed on the relationships between the renewable resources, conversion technology and economic feasibility along with consideration...
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Pumps, Turbines and Small Hydropower, LEC/LAB, ET, sem.7 winter 2023/24 (PG_00042108)
e-Learning CoursesThe aim of the course is to identify and demonstrate knowledge of the major concepts, theoretical perspectives, and historical trends in small hydropower. This course examines the principles of sustainability and renewable energy conversion with emphasis on hydro energy resources. Concentration is placed on the relationships between the renewable resources, conversion technology and economic feasibility along with consideration...
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Experimental Study of the Influence of Noise Level on the Uncertainty Value in a Measurement System Containing an Analog-to-Digital Converter
Open Research DataFor newly developed measuring systems it is easy to estimate type B uncertainties based on the technical data of the measuring modules applied. However, it is difficult to estimate A type un-certainties due to the unknown type and level of interferences infiltrating into the measuring sys-tem. This is a particularly important problem for measurements...
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Euilibrium composition of CH4-CO2-CO-H2-H2O-C system under various compositions syngas methanation with 20vol.% water vapour introduced
Open Research DataThe equilibrium compositions of CH4, CO2, CO, H2, H2O and C under the methanation reaction of various syngas mixtures (different CO/H2 ratio) were supplied with this dataset
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Experimental tests of lintel hybrid beams
PublicationThe results of experimental tests of lintel hybrid beams made of air concrete and prestressed concrete were presented in paper. Blocks of air concrete was a protective element for the construction one. The length of hybrid beams was 3.0 m, while total height 27 cm. It was assumed that hybrid beams will work in the simply-supported scheme (with a 10 cm support) loaded uniformly over the entire length. The object of the tests were...
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Mathematical Modeling of the Impact Range of Sewage Discharge on the Vistula Water Quality in the Region of Włocławek
PublicationThe paper presents results of analysis of the industrial sewage discharge influence at km 688 + 250 of the Vistula River on water quality. During the analysis, two-dimensional models of flow, impurities and temperature transport were used. Hydrological conditions of the analyzed section of the river, characteristic flows and bathymetry of the riverbed in the first instance were defined. Calculations of velocity distribution at...
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Analytical model with non-adiabatic effects for pressure drop and heat transfer during boiling and condensation flows in conventional channels and minichannels
PublicationIn the paper a method developed earlier by authors is applied to calculations of pressure drop and heat transfer coefficient for boiling flow and condensation flow with account of non- adiabatic effects for some recent data collected from literature. The first effect, the modification of interface shear stresses in annular flow pattern is considered through incorporation of the so called "blowing parameter". The mechanism of...
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Magnetic-dipole-to-electric-quadrupole cross-susceptibilities for relativistic hydrogenlike atoms in some low-lying discrete energy eigenstates
PublicationIn this paper we present tabulated data for magnetic-dipole-to-electric-quadrupole cross-susceptibilities (χ_{M1→E2}) for Dirac one-electron atoms with a pointlike, spinless and motionless nucleus of charge Ze. Numerical values of this susceptibility for the hydrogen atom (Z = 1) and for hydrogenic ions with 2 \leqslant Z \leqslant 137 are computed from the general analytical formula, recently derived by us (Stefanska, 2016), valid...
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Potential energy curves, transition and permanent dipole moments of KRb
PublicationWe present extensive calculations of 48 adiabatic potential energy curves of the KRb molecule. Efforts have been focused on preparing the appropriate basis sets. Compared to previous approaches, the set of new potential energy curves is extended to higher excitations, including the single-excited K(4s2S)+Rb(5d2D) and double-excited K(4p2P)+Rb(5p2P) atomic limits. Larger distances between nuclei are also taken into account. New...
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Tuning of the plasmon resonance location in Au nanostructures coated with a ultrathin film of Al2O3 – Optical measurements and FDTD simulations
PublicationThe Au nanostructures have been coated with an ultra-thin films of amorphous aluminium oxide. Optical absorption spectra show the influence of the thickness of Al2O3 on plasmon resonance wavelength. The observed red-shift of the resonance location with the increase of the thickness of the Al2O3 film, can be explained by the change in the dielectric function of this film. It allows control of the optical spectra of the coated particles....
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Low-energy positron scattering from DNA nucleobases: the effects from permanent dipoles
PublicationAb initio quantum calculations for low-energy positron scattering from gas-phase isolated molecular nucleobases which are part of the DNA structure are presented and discussed over the range of 1 eV to 25 eV. The calculations report the integral cross sections (ICSs) and the momentum-transfer cross sections (MTCSs) for Adenine, Guanine, Thymine and Cytosine. The calculations show very clearly the important role of the dominant...
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HYDROGEN PRODUCTION PERFORMANCE IN THERMOCATALYTIC REACTOR BASED ON THE INTERMETALLIC PHASE OF NI3AL
PublicationThe main aim of the following paper is mathematical modelling for momentum, heat and mass transfer, which is accompanied by chemical surface reactions of the flow of the mixture helium and methanol. The thermocatalytic devices used for decomposition of hydrocarbons incorporate vertical microchannels coupling at the ends and heated to 500 oC at the walls. The results of the experiment were compared with CFD calculations to calibrate...
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Buckling of simplified models of silo with corrugated walls and vertical stiffeners
PublicationThe paper deals with buckling of cylindrical silos composed of corrugated sheets and vertical stiffeners (columns). Comprehensive finite element analyses were carried out for a perfect silo by means of a linear buckling approach. Corrugated walls were simulated as an equivalent orthotropic shell and vertical thin-walled columns as beam elements. Calculations for perfect silos with different numbers of columns made it possible to...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.0, b=0.11) and (C=5.7, b=0.32) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.4, b=0.26) and (C=2.1, b=0.14) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.1, b=0.14) and (C=5.7, b=0.32) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.0, b=0.11) and (C=2.1, b=0.14) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=5.5, b=0.37) and (C=5.7, b=0.32) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.1, b=0.14) and (C=5.5, b=0.37) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.0, b=0.11) and (C=5.5, b=0.37) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.8, b=0.25) and (C=2.0, b=0.11) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.8, b=0.25) and (C=2.1, b=0.14) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.8, b=0.25) and (C=5.5, b=0.37) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.4, b=0.26) and (C=2.0, b=0.11) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.4, b=0.26) and (C=5.7, b=0.32) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.8, b=0.25) and (C=5.7, b=0.32) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.4, b=0.26) and (C=5.5, b=0.37) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=2.4, b=0.26) and (C=2.8, b=0.25) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two directional control valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first DCV -> ambient atmosphere, (2) being emptied...
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Determination of flow properties of a serial connection of two pneumatic elements with (C=4.40, b=0.42) and (C=7.30, b=0.49) from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for two pressure relief valves arranged in-line. Four test configurations were used: (1) being emptied tank -> the first PRV -> ambient atmosphere, (2) being emptied...