Filters
total: 2331
filtered: 1711
displaying 1000 best results Help
Search results for: ROTATIONAL FLOW METER
-
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 -
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.
-
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.
-
An Instantaneous Engine Speed Estimation Method Using Multiple Matching Synchrosqueezing Transform
PublicationInstantaneous rotational speed measurement of the engine is crucial in routine inspection and maintenance of an automobile engine. Since the contact measurement of rotational speed is not always available, the vibration measurement has been used for noncontact rotational speed estimation methods. Unfortunately, the accuracy of the noncontact estimation methods by analyzing engine vibration frequency is not satisfactory due to the...
-
Towards Designing an Innovative Industrial Fan: Developing Regression and Neural Models Based on Remote Mass Measurements
PublicationThis article presents the process of the construction and testing a remote, fully autonomous system for measuring the operational parameters of fans. The measurement results obtained made it possible to create and verify mathematical models using linear regression and neural networks. The process was implemented as part of the first stage of an innovative project. The article presents detailed steps of constructing a system to...
-
MACHINE VISION DETECTION OF THE CIRCULAR SAW VIBRATIONS
PublicationDynamical properties of rotating circular saw blades are crucial for both production quality and personnel safety. This paper presents a novel method for monitoring circular saw vibrations and deviations. A machine vision system uses a camera and a laser line projected on the saw’s surface to estimate vibration range. Changes of the dynamic behaviour of the saw were measured as a function of the rotational speed. The critical rotational...
-
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.
-
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 -
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.
-
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...
-
Spinning Fluids Reactor: A new design of a gas – liquid contactor
PublicationCurrent trends in chemical reactor design are based on adapting these to the requirements of a particular chemical process. Processes involving reactions between the gas and liquid phase in particular require precise adjustment of all parameters. The common denominator for most modern design solutions is enhancement of the mass transfer area and the overall volumetric mass transfer coefficient. Gas – liquid contactors evolved from...
-
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 -
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...
-
The effect of a miniature argon flow rate on the spectral characteristics of a direct current atmospheric pressure glow micro-discharge between an argon microjet and a small sized flowing liquid cathode
Publication -
Coupling of cold vapor generation with an atmospheric pressure glow microdischarge sustained between a miniature flow helium jet and a flowing liquid cathode for the determination of mercury by optical emission spectrometry
Publication -
Pulse-Modulated Radio-Frequency Alternating-Current-Driven Atmospheric-Pressure Glow Discharge for Continuous-Flow Synthesis of Silver Nanoparticles and Evaluation of Their Cytotoxicity toward Human Melanoma Cells
Publication -
Application of gas flow headspace liquid phase micro extraction coupled with gas chromatography-mass spectrometry for determination of 4-methylimidazole in food samples employing experimental design optimization
Publication -
Cavitation resistance of OH18N9 steel alloyed with vaidus amount of TiC or Mn by means of laser beam. XIV International Symposium on Gas Flow, Chemical Lasers and High Power Lasers.
PublicationPrzedstawiono badania odporności kawitacyjnej stali OH18N9T po laserowym stopowaniu jej powierzchni węglikiem TiC oraz manganem. Wykazano, że wzbogacenie obrabianej stali manganem powoduje przemiany fazowe pod wpływem działania obciążeń kawitacyjnych, co przyczynia się do wzrostu odporności kawitacyjnej. Wzmacnianie stali węglikiem TiC powoduje natomiast zanik zdolności stali do wzmacniania odkształceniowego.
-
Comparative study of high‑pressure fluid flow in densely packed granules using a 3D CFD model in a continuous medium and a simplified 2D DEM‑CFD approach. Granular Matter
PublicationIzotermiczny ściśliwy jednofazowy przepływ cieczy przez niejednorodną masę ziarnistą składającą się z gęsto upakowanych zachodzących na siebie kul imitujących skałę pod wysokim ciśnieniem zbadano numerycznie przy użyciu dwóch różnych podejść. Pierwsze podejście zwane pełnym modelem 3D CFD stosowało metodę skończonych objętości (FVM) do rozwiązania uśrednionego równania Naviera-Stokesa zakładając model naprężeń Reynoldsa (BSL) w...
-
Losses and energy efficiency of drive motors and systems
PublicationLosses and energy efficiency of every drive motor must be presented as functions of physical quantities independent of losses in the motor. Such quantities are speed and load required by the machine or device driven by the motor, changing in the drive operating field. Speed and load of the motor decide of the instantaneous useful power of the motor and also in a differentiated way of kinds and values of losses occurring in the...
-
Losses and energy efficiency of drive motors and systems
PublicationLosses and energy efficiency of every drive motor must be presented as functions of physical quantities independent of losses in the motor. Such quantities are speed and load required by the machine or device driven by the motor, changing in the drive operating field. Speed and load of the motor decide of the instantaneous useful power of the motor and also in a differentiated way of kinds and values of losses occurring in the...
-
VIBRATION DIAGNOSTICS OF FOOTBRIDGE WITH USE OF ROTATION SENSOR
PublicationThe benefits of the additional measurement of rotational degrees of free-dom on the performance of the vibration diagnosis of bridges are studied in this paper. The common vibrational diagnostics that uses translational degrees of freedom is extended by measurements of rotations. The study is curried out on a footbridge and the presence of damage as well as its location and size is determined with use of FEM updating procedure....
-
THE THERMODYNAMIC ANALYSIS OF THE SZEWALSKI HIERARCHIC VAPOUR CYCLE COOPERATED WITH THE SYSTEM OF HEAT RECOVERY
PublicationIn this paper, thermodynamic analysis of the Szewalski hierarchic vapour cycle cooperated with the system of heat recovery from exhaust gases are presented. According to that purpose, the CFM (Computation Flow Mechanics [1,3]) approach has correctly been used. The whole system consists of the first traditional steam cycle, the second organic Rankine cycle (ORC) and system of heat recovery with use of water with temperature 90...
-
The basics of design and experimental tests of the commutation unit of a hydraulic satellite motor
Publicationhe article presents an analytical method to design the commutation unit in a hydraulic satellite motor. It is shown that the size of the holes feeding the working chambers and their location on the plates closing those chambers depends on the geometrical dimensions of the working mechanism. The overlap in the commutation unit depends on the rotational speed range. It is demonstrated that the geometrical dimensions of the commutation...
-
Equations of tribological parameters for liquid flow in boundary layer on the tissue surface in bioreactor = Wyznaczanie parametrów tribologicznych dla przepływu cieczy w warstwie granicznej na powierzchni tkanki w bioreaktorze
PublicationW niniejszej pracy przedstawiony został problem tribologiczny wynikający z przepływu nieustalonego odżywczej cieczy lepkiej w cienkiej warstwie przyściennej w bezpośrednim kontakcie z zewnętrzną powierzchnią warstwy wierzchniej wzrastających komórek (chondrocytów) w trakcie procesu ich hodowli w bioreaktorze. Efektem rozważań będą wartości sił tarcia powstające na powierzchni wzrastającej tkanki. Najnowsze badania wykazały lepszą...
-
Simulations of high-pressure fluid flow in a pre-cracked rock specimen composed of densely packed bonded spheres using a 3D CFD model and simplified 2D coupled CFD-DEM approach
PublicationW artykule zastosowano dwa różne podejścia do opisu jednofazowego przepływu płynu w wstępnie spękanej próbce skały o niskiej porowatości pod wysokim ciśnieniem. Głównym celem pracy było bezpośrednie porównanie rozkładu ciśnień, gęstości i prędkości płynów we wstępnie pękniętej próbce. Zachowanie próbki imitującej skałę zostało opisane przez gęsto upakowane połączone kohezją kulki z nakładającymi się na siebie elementami. Pierwsze...
-
Dependence of Housing Real Estate Prices on Inflation as One of the Most Important Factors: Poland’s Case
PublicationThe study aimed to examine the impact of inflation on the real estate market using Polish panel data for the last 13 years. It is based on a panel model, where price changes of one square meter of housing are determined as a function in changes of inflation, the central bank's base rate, dwellings built, as well as new mortgage loans. The quarterly dynamics of the average price of 1 square meter of housing in...
-
Impulse Impedance Measurements of Lightning Protection Earthings
PublicationLightning protection earthing systems should be tested at currents with time parameters similar to those of lightnings. A method and definition of a measured value of impulse impedance are introduced. The impulse impedance was determined by a quotient of voltage drop on the tested earthing to a value of current in measure circuit. The usefulness of the impulse method for lightning protection evaluation is tested on radio base stations...
-
Comparison of Mathematical Models of Torque Transmitted by Multi-disc Wet Clutch with Experimental Results
PublicationIn this article was described the methodology for the experimental study of flows in the prototype of a satellite hydraulic motor with a rotating body. The experimental tests of the motor were carried out at a low constant rotational speed in a wide range of pressure drop in this motor. The constant rotational speed of the motor was kept by a worm gear. Based on the test results, the leakage characteristics in the flat gaps of...
-
On the internal efficiency of a turbine stage: classical and CFD definitions
PublicationAlmost entire fleet of steam turbines in Poland was designed between 1950 – 1980 with the use of the so-called zero dimensional (0D) calculation tools. For several years, design and modernization of the turbines occur in assistance with the state of the art methods that describe working fluid flow field based on 3D models and CFD codes. This cooperation between 0D and 3D codes requires exchange of overall, integral information...
-
Optical Emission Spectroscopy of Microwave (915 MHz) Plasma in Atmospheric Pressure Nitrogen with Addition of Ethanol Vapour
PublicationIn this paper results of optical emission spectroscopic study of microwave 915 MHz plasma in atmospheric pressure nitrogen with an addition of ethanol vapour are presented. The plasma was generated in waveguide- -supplied cylinder-type nozzleless microwave plasma source. The aim of research was to determine the rotational Trot and vibrational Tvib temperatures of CN and C2. A method called bubbling was employed to introduce alcohol (ethanol)...
-
Analiza przepływu oleju przez rowek smarowy wzdłużnego łożyska ślizgowego z wykorzystaniem komputerowej dynamiki płynów (CFD) = Analysis of the lubricant flow through the hydrodynamic thrust bearings groove with the use of computational fluid dynamic
PublicationSmarowanie zanurzeniowe jest tradycyjnym sposobem smarowania wzdłużnych łożysk ślizgowych. Jednak rozwiązanie to wykazuje umiarkowaną skuteczność w zapewnieniu optymalnie niskich temperatur w filmie smarowym a ponadto jest przyczyną strat mocy związanych z mieszaniem oleju w obudowie łożyska, co jest szczególnie widoczne w łożyskach szybkoobrotowych. Obecnie wymagania stawiane nowym konstrukcjom łożysk ślizgowych to zwiększanie...
-
Automatic system for optical parameters measurements of biological tissues
PublicationIn this paper a system allowing execution of automatic measurements of optical parameters of scattering materials in an efficient and accurate manner is proposed and described. The system is designed especially for measurements of biological tissues including phantoms, which closely imitate optical characteristics of real tissue. The system has modular construction and is based on the ISEL system, luminance and color meter and...
-
The modyfication of the dynamic characteristics of vibratory conveyor
PublicationThe vibratory conveyors are used in the industry for continuous transportation of loose substances on distance up to 20meters. These conveyors are often suspended on expensive and massive frames, which are softly vibroisolated from the ground. As a result, they transfer significant dynamic forces on the ground. In case of 5 - 20 meter-long devices, the biggest construction problems are proper vibrations of the panel caused by bilateral...
-
Small Vessel with Inboard Engine Retrofitting Concepts; Real Boat Tests, Laboratory Hybrid Drive Tests and Theoretical Studies
PublicationThe development of modern technologies and their increasing availability, as well as the falling costs of highly ecient propulsion systems and power sources, have resulted in electric or hybrid propulsions systems’ growing popularity for use on watercraft. Presented in the paper are design and lab tests of a prototype parallel hybrid propulsion system. It describes a concept of retrofitting a conventionally powered nine meter-long...
-
On analysis of nanocomposite conical structures
PublicationThis research examines the analysis of rotating truncated conical baskets reinforced by carbon nanotubes around the two independent axes. A time-dependent analysis is considered, and the nonlinear dynamic governing equations are extracted using the energy method. Carbon nanotubes (CNTs) reinforced the conical basket, and the structure's mechanical properties are determined based on the several distributions of carbon nanotubes....
-
Negative impact of constant RPM control strategy on ship NOx emission in waves
PublicationIn severe wave conditions, the ship propulsion system is loaded with high fluctuations due to external disturbances. The highly fluctuating loads enforce radical changes in the main engine torque, which in turn demands variation of the fuel rate injected into the cylinders if a constant rotational speed strategy is applied. Therefore, the temperature of gases varies to a large extent during the combustion process in the cylinders....
-
Noise emitted by SKM Trains in Gdansk
PublicationHigh intensity traffic of SKM trains in Gdansk carries a significant level of noise emission. SKM line runs through the central part of the city and therefore in the vicinity of residential areas and recreational facilities. This research was planned and performed to find out what was the real noise emission of SKM trains and to determine whether the measurement noise values are within allowed limits. Individual acoustic events...
-
[Chapter] 22. Application of physical modeling to study combustion process-es and flow patterns in large-scale boilers and furmaces. W: Optical me- thods and data processing in heat and fluid flow. Ed. C. Greated, J. Cos-grove, J.M. Buick. Bury St. Edmunds. London: Profess. Eng. Publ.**2002 s. 267-277, 4 rys. bibliogr. 6 poz. Zastosowanie modelowania fizycznego do badania procesów spalania pola prze- pływu w przemysłowych kotłach i piecach.
PublicationRozdział zawiera wyniki badań modelowania fizycznego dwuwymiarowego i trój-wymiarowego pola przepływu i procesów spalania w wybranych urządzeniachprzemysłowych.
-
Effect of the Cavitation Generation Unit Structure on the Performance of an Advanced Hydrodynamic Cavitation Reactor for Process Intensifications
PublicationThe advanced rotational hydrodynamic cavitation reactors (ARHCRs) that appeared recently have shown obvious advantages compared with conventional devices in process intensifications. In ARHCRs, the cavitation generation unit (CGU) located on the rotor and stator basically determines their performance. For the first time, the present study investigated the effect of the CGU structure on the performance of a representative ARHCR...
-
A Compact and Lightweight Microwave Tilt Sensor Based on an SRR-Loaded Microstrip Line
PublicationIn this paper, the symmetry property of split ring resonators (SRRs) is exploited to develop a tilt sensor. The sensor is composed of an SRR-loaded microstrip line operating at microwave frequencies. It is shown that the depth of notch in the reflection characteristic of the microstrip is a function of the tilt angle of the SRR. Thus, it can be used for sensing inclination. The sensor benefits from very compact size and light weight....
-
A BODIPY‐Based Molecular Rotor in Giant Unilamellar Vesicles: A Case Study by Polarization‐Resolved Time‐Resolved Emission and Transient Absorption Spectroscopy
PublicationBODIPY and BODIPY-derived systems are widely applied as fluorophores and as probes for viscosity detection in solvents and biological media. Their orientational and rotational dynamics in biological media are thus of vital mechanistic importance and extensively investigated. In this contribution, polarization-resolved confocal microscopy is used to determine the orientation of an amphiphilic BODIPY-cholesterol derivative in homogeneous...
-
Complex Monitoring of the Coastal Cliffs on the Example of Cliff in Jastrzebia Gora, Poland
PublicationThe cliff coasts, which are in total about 100 km long, are especially vulnerable to abrasion. The mean regression of the studied object which is the seacliff in Jastrzebia Gora depends on time. For example, from 1875 to 1937 the cliff regress 90 m in mean pace of 1.4 meter a year. Besides of natural factors causing the degradation, there is also an anthropogenic activity, which speeds up the abrasion process. Based on these informations,...
-
The buckling analysis of a cold-formed steel C-sectional column resting on an elastic foundation
PublicationThe paper is focused on stability analysis of different models of steel cold-formed C-section column. The analysed element may be applied as a primary load-bearing member in steel trusses or silo columns. The column can be used as a support for a wall of roof plates made of corrugated sheets. The wall sheeting that restrains the column against buckling may be considered as an elastic foundation. Due to the design solutions the...
-
Liquid residence time in vortex separators
PublicationCentrifugal force enhances gravitational separation of suspension (vortex separators), as well as allows regulation of liquid discharge (vortex flow controls). Furthermore, it elongates the effective residence time of liquid inside the chamber in comparison to non-circulative flow. Laboratorz measurements, described in the paper, indicate that average liquid residence time for circulative flow exceeds 50% of plug-flow time,...
-
Effects of Column Base Flexibility on Seismic Response of Steel Moment-Frame Buildings
PublicationSteel Moment Resisting Frames (SMRFs) are very popular lateral load resisting systems in many seismically active regions. However, their seismic response is strongly dependent on the rotational fixity of column base connections. Despite many studies (both experimental and numerical) in this particular area, available approaches for estimating column base flexibility have been validated only against laboratory test data. In the...
-
Failure analysis of a high-speed induction machine driven by a SiC-inverter and operating on a common shaft with a high-speed generator
PublicationDue to ongoing research work, a prototype test rig for testing high-speed motors/generators has been developed. Its design is quite unique as the two high- speed machines share a single shaft with no support bearings between them. A very high maximum operating speed, up to 80,000 rpm, was required. Because of the need to minimise vibration during operation at very high rotational speeds, rolling bearings were used. To eliminate...
-
Theoretical and Actual Feed Per Tooth During Wood Sawing on an Optimizing Cross-Cut Saw
PublicationThe work presents the geometries of circular saw teeth, whose task is to divide the cross-cut of the cutting layer. For efficient machining on a cross-cut saw with high feed speed values (about 1 ms−1) maximal theoretical feeds per tooth are determined. These values were compared with the actual values determined during transverse cutting of pine wood on a special test stands in industrial conditions. In the experiment the rotational...