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EN
The paper presents the methodology for designing the injection shaft drive for diesel engines with 2,3,4,6 and 8 cylinders as well as power from 2.5 to 52 kW per cylinder using the FEM method and experimental research. The pump is the original solution of the authors. The shaft is a basic part of the pump with a complex structure. In order to assess the state of stress in the shaft, the FEM analytical method was used and experimental tests were carried out, subjecting the shaft to torsional moment resulting from the transmitted power. Experimental studies confirmed the results of numerical calculations and the correctness of the adopted solution. The destructive tests were carried out to assess the maximum load capacity of the shaft, loading it with an increasing torque until visible plastic deformations occurred. This condition appeared at twice the moment (Ms = 602 Nm) in relation to the maximum predicted moment in operation (extreme operating conditions of the pump shaft). The theoretical studies confirmed very significant stress concentration (αk coefficient at the level of 2.63 or even 4.7), which may be the cause of fatigue cracks. It also determines the strength of the shaft and its torsional stiffness, which influences the proper functioning of the pump and ensures adequate fuel injection phases.
PL
W artykule opisano wpływ najczęściej popełnianych błędów w trakcie montażu stalowych łączników rozporowych na nośność zamocowań. Zazwyczaj wynika to z zarysowań podłoża betonowego, użycia wierteł o niewłaściwej średnicy, zastosowania nieodpowiedniego momentu instalacyjnego, zbyt płytkiego osadzenia łączników w podłożu itp. Stwierdzone w badaniach różnice w nośności mogą dochodzić nawet do 200%.
EN
The paper describes the effects of errors most frequently met while installing the metal anchors on the bearing capacity of the fixing system. It is usually caused by cracks of the concrete base, usage of drills with incorrect diameters, application of improper installation torque and/or too shallow embedment of anchors in the concrete base, and also other factors. The differences in the capacity found in the tests can reach even 200%.
EN
This experimental study investigated the effects of a conventional cutting fluid during drilling cylindrical holes on workpiece materials made of the AISI 1040 steel. Drilling responses were compared between dry and wet (in presence of the cutting fluid) cutting conditions with respect to drilling force, roundness deviation and taper of the hole, and chip morphology. High production machining and drilling with high cutting speed, feed, and depth of cut were found to be inherently associated with the generation of a large amount of heat and high cutting temperature. In a dry condition such high cutting temperature not only reduces dimensional accuracy and tool life but also impairs the roundness deviation and taper of the hole. The use of a conventional cutting fluid, in such a situation, was very effective to reduce the cutting temperature. In a dry cutting condition, numerous tool-wears were found on the drill bits. Drilling in such a dry condition seriously affects roundness of the hole, and chip shape and color. Contrastingly, use of a traditional cutting fluid reduced temperature as well as improved roundness and taper of the hole. It also acted as a lubricate at the tool tip–work surface interface. Overall, the conventional cutting fluid enhanced the quality of the machine work and potentially can increase machine life of drill bits.
EN
An attempt is made in the current research to obtain the fundamental buckling torque and the associated buckled shape of an annular plate. The plate is subjected to a torque on its outer edge. An isotropic homogeneous plate is considered. The governing equations of the plate in polar coordinates are established with the aid of the Mindlin plate theory. Deformations and stresses of the plate prior to buckling are determined using the axisymmetric flatness conditions. Small perturbations are then applied to construct the linearised stability equations which govern the onset of buckling. To solve the highly coupled equations in terms of displacements and rotations, periodic auxiliary functions and the generalised differential quadrature method are applied. The coupled linear algebraic equations are a set of homogeneous equations dealing with the buckling state of the plate subjected to a unique torque. Benchmark results are given in tabular presentations for combinations of free, simply-supported, and clamped types of boundary conditions. It is shown that the critical buckling torque and its associated shape highly depend upon the combination of boundary conditions, radius ratio, and the thickness ratio.
EN
The unique properties of magnetic fluids result from their ability to undergo reversible, almost immediate, changes in their rheological properties under the influence of magnetic fields as well as the possibility to position them by magnetic field forces. It is also possible to control the direction and flow rate of such fluids. These properties provide an efficient way to develop new types of controllable machines and devices, such as brakes, clutches and bearings. The objective of the study was to examine the axial force and torque friction of a magnetorheological (MR) fluid working in the shear flow mode (parallel plate system) subjected to different magnetic induction ramp profiles. The rotation speed and working gap height were also taken into account. Determining the response of the tested system to magnetic induction change in different working conditions was of particular interest.
EN
In the most developed countries, intensive studies are being carried out to utilize various types of electric machines such as synchronous motors with permanent magnets and traction motors with non-traditional magnetic systems on traction electric drives. Switched Reluctance Motors (SRM) are one of the most simple, reliable, and cost-efficient technology used in manufacture and operation. Its convenient traction performance, combined with the high overload capacity, makes its use promising for both freight and passenger rolling stock. Our research is directed to develop a control system for a four-phase SRM. The procedure of fuzzy-regulator synthesis is presented. A physical model of a switched reluctance drive is created, namely, it is a system of a wheel set and a motor. The efficiency of the control system with different types of speed regulators was checked and their main quality indicators were determined. According to the results of the analysis, it was found that the fuzzy regulator more precisely controls the regulated value.
EN
The article describes processing method of a signal, coming from torsional deflections of an internal combustion piston engine’s crankshaft, registered using two optical encoders ETNP-10. Standard measurement and recording set ETNP-10 enables recording of Instantaneous Angular Speed values encompassing 10 revolutions of the crankshaft, what is equal to 5 cycles of four-stroke engine. That time duration is sufficient for analysis of changes of angular speed caused by, for example, malfunction of fuel injection valve, but is insufficient in case of observation characterized by low frequency changes with period of fluctuations, lower than 0.8 sec. Short time for recording makes impossible following of instantaneous angular speed deviations caused by magnitude modulation of engine’s load value. In the article is presented an algorithm written in MATLAB environment, which allows processing of the data recorded using the recorder DAS 1600 Sefram. The recorded this way signals have around 26 seconds' duration of engine work. Data acquired from two encoders mounted at opposite sides of the shaft, in form of square magnitude signals are transformed into instantaneous speed and subsequently to instantaneous angular shift, what is basis for torsions calculation. In the article is also presented method of elimination of systematic error due to assumed method of averaging. Finally, some examples of results of torsional deflection measurement and analysis are presented.
EN
Continuous monitoring of diesel engine performance under its operating is critical for prediction of malfunction development and subsequently functional failure detection. Analysis of Instantaneous Angular Speed (IAS) of the crankshaft is considered as one of non-intrusive and effective method of detection of combustion quality deterioration. The article contains presentation of attempt of monitoring of piston engine’s crankshaft torsional vibrations by measurement of Instantaneous Angular Speed at free, and power output ends of the engine’s crankshaft. The angular speed measurements was done using two optical sensors for reading the IAS, mounted at shaft line’s opposite ends, one at free end of the crankshaft and second at end of generator’s shaft. In the article is presented description of the measurement system and explanation of its mode of work. Experiments were based at two kinds of malfunction possible to be simulated at test bed. First one was simulation of a leak of fuel injection pump, the second one relayed on mounting of sets of injection valves with different nozzles characteristics (spraying nozzle angle), giving different parameters of fuel injection. Presented results of experiment derives from test cycle carried out using laboratory stand of Gdynia Maritime University equipped with 3- cylinder self − ignition engine, powering electric generator.
PL
W artykule przedstawiono analizę wpływu zmiany kąta kształtującego α na wartości parametrów siłowych w procesie walcowania skośnego. Przeprowadzona symulacja numeryczna kształtowania odkuwki stopniowanego wału umożliwiła przedstawienie rozkładów siły promieniowej i osiowej, jak również rozkładu momentu obrotowego działających na rolkę stożkową w zależności od ustalonego kąta kształtującego α.
EN
The paper presents a numerical investigation of the effect of the forming angle α value change on force parameters in a skew rolling process. The MES simulation of forming the stepped shaft allows for the presentation of radial and axial force distributions, as well as the distribution of torque acting on the conical roller, depending on the determined forming angle α.
PL
W artykule przedstawiono analizę wpływu zmiany kąta kształtującego α na wartości parametrów siłowych w procesie walcowania skośnego. Przeprowadzona symulacja numeryczna kształtowania odkuwki stopniowanego wału umożliwiła przedstawienie rozkładów siły promieniowej i osiowej, jak również rozkładu momentu obrotowego, działających na rolkę stożkową, w zależności od ustalonego kąta kształtującego α.
EN
The paper presents a numerical investigation of the effect of the forming angle α value change on force parameters in a skew rolling process. The MES simulation of forming the stepped shaft allows for the presentation of radial and axial force distributions, as well as the distribution of torque acting on the conical roller, depending on the determined forming angle α.
11
Content available remote Zadawanie i programowa kontrola obciążeń w rehabilitacji narządów ruchu
PL
Urządzenia rehabilitacyjno-diagnostyczne służą do rzetelnej i obiektywnej oceny postępów podczas rehabilitacji pacjenta. Autorzy niniejszego artykułu opracowali koncepcje układu sterująco-pomiarowego do zadawania i kontroli obciążenia badanego stawu z wykorzystaniem modułu akwizycji danych NI 6351 oraz środowiska labVIEW firmy National Instruments.
EN
Rehabilitation and diagnostic devices can be used to assess progress objectively in during rehabilitation of patient. The authors of this article have developed concepts of control and measuring unit. The system allows controlling load torque of joint and muscles limbs. The authors used data acquisition module NI 6351 and development environment LabVIEW from National Instruments.
EN
The following article is devoted to research on particular operational characteristics of prototypes of rotating magnetorheological clutches and brakes. The experiments were conducted on a specialized test stand, including a high power servo-motor, torque meters, and thermal sensors. In addition to the generally determined relationship of the clutch or brake torque transmitted over time and depending on the electric current, it has been shown that the particular operational characteristics of these devices are necessary for the full operational picture of the performance of the device. These are, among others, the torque versus rotational speed, temperature, and operational time dependencies.
PL
Praca poświęcona jest badaniom prototypów sprzęgieł i hamulców magnetoreologicznych pracujących w ruchu obrotowym. Zostały one przeprowadzone na specjalistycznym stanowisku badawczym. Obok powszechnie wyznaczanych zależności przenoszonego momentu obrotowego sprzęgła lub hamulca w funkcji czasu i w zależności od wartości natężenia prądu płynącego w solenoidach tych urządzeń i sterującego natężeniem pola magnetycznego wytwarzanego wokół cieczy magnetoreologicznej wykazano, że do pełnego obrazu eksploatacyjnych warunków pracy niezbędne jest wyznaczenie dodatkowych charakterystyk tych urządzeń. Są nimi między innymi wyznaczane w pracy charakterystyki ilustrujące zależności momentu obrotowego w funkcji obrotów, temperatury i inne.
PL
W pracy przeprowadzono porównanie parametrów trakcyjnych m. in. takich jak moc, przyspieszenie czy prędkość ciągnika siodłowego marki Scania serii R w oryginale i po przeprowadzonym chip tuningu. Wyniki porównań zestawiono w formie wykresów.
EN
In the work a comparison of traction parameters such as power, acceleration or speed of Scania R series truck in the original and after the chip tuning was performed. Comparison results are presented in graphs.
PL
W pracy przeprowadzono porównanie parametrów trakcyjnych m. in. takich jak moc, przyspieszenie czy prędkość samochodu marki Skoda Fabia 1.6 TDI 77kW w oryginale i po przeprowadzonym chip tuningu. Wyniki porównań zestawiono w formie wykresów.
EN
In the work a comparison of traction parameters such as power, acceleration or speed of Skoda Fabia 1.6 TDI 77kW car in the original and after the chip tuning was performed. Comparison results are presented in graphs.
PL
Przy badaniach obracających się zespołów i maszyn, głównie, ale nie tylko dla oceny ich zdolności wytwarzania mocy lub jej strat, potrzebny jest wiarygodny pomiar momentu obrotowego. Pomiar tej istotnej wielkości fizycznej towarzyszy nie tylko badaniom stanowiskowym, lecz wykorzystywany jest on również w seryjnych pojazdach samochodowych, chociażby w przekładniach kierowniczych czy do sterowania skrzyniami biegów[1]. Istnieje wiele czynników zakłócających ten pomiar. Część z nich w wielu przypadkach jest niemożliwa do zdefiniowania, a nawet pośród tych czynników zakłócających, które zostały określone, redukcja ich do poziomu w pełni zadawalającego jest z reguły niemożliwa. W związku z powyższym, sygnał momentu obrotowego często zostaje poddany różnego typu opracowaniu zanim zostanie np. wysłany do sterownika . W tym celu stosuje się m.in. rozmaite rodzaje filtrów bądź opracowania statystyczne, pośród których najprostszym przykładem jest uśrednianie arytmetyczne. W artykule po przedstawieniu najpopularniejszych źródeł zakłóceń i metod walki z nimi, omówiona została propozycja metody uśredniania momentu obrotowego w trakcie pomiaru. Pomimo, iż pomiary z uśrednianiem wartości mierzonej z reguły mogą być stosowane do przebiegów statycznych/wolnozmiennych, opisana propozycja metody pomiaru nadaje się do pomiarów zmiennych/dynamicznych, gdyż uśrednianie zachodzi w ramach jednego obrotu wału. Przedstawiono opis propozycji, przebiegi wartości momentu obrotowego bez jakiegokolwiek opracowania oraz z zastosowaniem autorskiej metody. W zakończeniu sformułowano wnioski wynikające z przedstawionych wyników badań.
EN
Reliable and repeatable torque measurement is a crucial issue during every research and in every kind of system which operation is based on torque value. Although the progress is done in the science last years, accurate torque measurement is still a problematic issue. After discussing the most popular sources of noise, article describes the authors’ proposal of torque value averaging method during the tests. Despite the fact, that the most of averaged measurements can be used in the static processes, this method is useful also in dynamic measurements because the averaging is performed within one revolution. Description of the method is included, test results without and with proposed data averaging are presented. Summary contains conclusions based on the presented results.
EN
Skew rolling is a metal forming technique which can be used for producing stepped axles and shafts. This paper investigates seventeen cases of rolling at varying process parameters by the finite element method. As a result, it is possible to determine the effect of the forming angle α, skew angle Θ, linear velocity of the chuck, v, billet temperature, T, rotational speed of the rolls, n, reduction ratio, δ and friction factor, m, on axial load (acting on the chuck), radial load (acting on the roll in the radial direction) and torque. The results will be used when designing a laboratory stand for skew rolling which will be constructed at the Lublin University of Technology.
17
Content available Superconducting Wind Turbine Generators
EN
Wind energy is well known as a renewable energy because its clean and less polluted characteristic, which is the foundation of development modern wind electricity. To find more efficient wind turbine is the focus of scientists around the world. Compared from conventional wind turbines, superconducting wind turbine generators have advantages at zero resistance, smaller size and lighter weight. Superconducting wind turbine will inevitably become the main trends in this area. This paper intends to introduce the basic concept and principle of superconductivity, and compare form traditional wind turbine to obtain superiority, then to summary three proposed machine concept.While superconductivity have difficulty in modern technology and we also have proposed some challenges in achieving superconducting wind turbine finally.
EN
An approach to determination of power efficiency of a switched reluctance motor (SRM) based on indirectly measured value of the torque is substantiated. A method for indirect determination of electromagnetic torque with the use of the results of measuring the instantaneous values of phase currents and voltages is presented. The most efficient and the factual angles of phase switching for the analyzed four-phase 8/6 SRM are determined. Comparison of SRM torque values obtained by calculation and by experiment is performed. Efficiency of the analyzed SRM is assessed on the basis of calculated values of the torque.
PL
W pracy wykazano, że podejście do wyznaczenia współczynnika sprawności silnika z przełączalną reluktancją w oparciu o niebezpośrednio mierzone wartości momentu jest uzasadnione. Przedstawiono metodę niebezpośredniego wyznaczenia momentu elektromagnetycznego poprzez pomiary chwilowych wartości prądu i napięcia fazowego. Wyznaczono najbardziej efektywne i faktyczne kąty przełączania fazy w czterofazowym silniku 8/6. Porównanie wartości momentu uzyskanego w obliczeniach i poprzez eksperyment wskazuje na to, że sprawność badanych silników może być oceniana w oparciu o obliczane wartości momentu.
19
Content available remote Pomiar i możliwość śledzenia przebiegu momentu w dużych układach napędowych
PL
Biorąc pod uwagę szeroki zakres możliwości pomiaru momentu obrotowego, metoda uwzględniająca przetwornik momentu obrotowego skalibrowany w miejscu wykonania z określoną dokładnością, która odnosi się do udokumentowanego, nieprzerwanego łańcucha porównań dotyczących zależności tego przetwornika momentu względem pierwotnego standardu, zapewnia możliwość śledzenia momentu.
EN
This paper presents the experimental research and simulating results of a ZM130 hydrodynamic torque converter under steady and unsteady working conditions with an external step signal and sinus on turbine’s shaft on a modified test bench. The mathematical model of torque converter was described by the one-dimensional flow theory with variable loss coefficients. The character of received equations from test bend showed by linearized transmittance functions with variable coefficients. For test bend object identification researches will be used an Identification Toolbox from a mathematical code in Matlab, which enables to create transfer functions as a linear model from measurements data as they got the highest correctness level with input signal (as they get the best correction level with input signal on the pump´s shaft). This mathematical model for dynamic loads will be verified by experimental tests. The aim of the carried out studies was determination the effect of sampling time decreasing on the quality of measured parameters. Results of present investigations were compared with those obtained earlier, but for the same input signals .It is possible to affirm that proposed theoretical model imitates the change of dynamic parameters, and the same the property of the torque converter. Researches led on the test bend with extortion input torque sinus signal on the turbine’s shaft confirmed correctness of this model.
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