Wyniki wyszukiwania - Biblioteka Nauki

1

Wpływ warunków fizycznych na proces separacji w cieczach magnetycznych

100%

Brożek M. , Pawlos W.

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2000

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tom z. 245

35-47

PL

W artykule podano podstawy teoretyczne procesu separacji w cieczach magnetycznych. Parametrami fizycznymi charakterystycznymi dla ww. separacji mającymi bezpośredni i najistotniejszy wpływ na tor ziarna w separatorze MGM mają: natężenie pola magnetycznego H, jego rozkład gradH2, własności medium (co, ro), w którym odbywa się separacja, oraz własności fizyczne spawanego surowca (c, r). Do analitycznego wyznaczenia toru ruchu ziarna w separatorze MGM wykorzystano równanie Newtona. Zaprezentowano doświadczalne tory ruchu ziaren dwuskładnikowych.

EN

On the paper theoretical bases of separation process in magnetic liquids have been given. He most important influence on the trajectory of a particle in magnetogravimetric (MGM) separator have such physical parameters as: magnetic field intensity H, its distribution gradH2, properties magnetic liquids (co, ro), in which a separation takes places as well as physical features of separated particles (c, r). For the analytical determination of the trajectory of a particle in the magnetogravimetric (MGM) separator Newton's equation has been used. Experimental trajectories of particle of two-component mixtures have been presented.

2

Przetworniki elektromagnetyczne z cieczą magnetyczną

75%

Szeląg W.

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2006

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tom Nr 51

65-84

PL

W artykule przedstawiono ciecze reologiczne o właściwościach sterowanych polem magnetycznym oraz wskazano ich zastosowania w przetwornikach elektromagnetycznych. Zaprezentowano przetworniki opracowane na Politechnice Poznańskiej. Do analizy stanów pracy przetworników z cieczą magnetyczna zaproponowano model polowy nieustalonych zjawisk sprzężonych: elektromagnetycznych, hydrodynamicznych, cieplnych oraz mechanicznych. Przedstawiono opracowany algorytm i program symulacji zjawisk sprzężonych w hamulcach magnetoreologicznych. Zaprezentowano wybrane wyniki symulacji i badań hamulca modelowego.

EN

The paper deals with magnetic fluids whose properties change in the presence of a magnetic field and shows how they can be applied in electromagnetic transducers. The electromagnetic brakes and dampers with magnetorheological fluid made in Poznań University of Technology has been shown. A field model of coupled electromagnetic, hydro-dynamic, thermodynamic and mechanical motion phenomena in brake with magnetic fluid is presented. The numerical implementation of the mathematical model is based on the finite element method and a step-by-step algorithm. Saturation, eddy currents, rotor movements, non-linear properties and the flow of the fluid have been taken into account. A computer program based on this algorithm was used to simulate the transients in a prototype of magnetorheological brake. The results of the calculations and measurements are presented.

3

Badanie zaworu magnetycznego rozruchowego sprzęgła hydrokinetycznego z cieczą magnetyczną

75%

Kęsy Z.

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2010

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tom nr 1

27-30

PL

Opisano koncepcję budowy sterowanego sprzęgła rozruchowego opartego na sprzęgle hydrokinetycznym z komorą dodatkową. Wskazano na zastosowanie zaworu magnetycznego z cieczą magnetyczną.

EN

In this paper an idea of new type of a starting hydrodynamic clutch was presented. This new clutch is based on the coupling with an additional chamber. Primary function of the magnetic valve is to control of working magnetic fluid volume inside the clutch impellers.

4

Symulacja drgań belki kompozytowej z cieczą magnetyczną

63%

Lara-Prieto V. , Kęsy Z. , Parkin R. , Jackson M. , Silberschmidt V.

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2010

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tom R. 83, nr 1/S

255-262

PL

Przedstawiono obliczenia numeryczne wykonane za pomocą programu ANSYS 11.0, dotyczące wpływu natężenia pola magnetycznego na częstotliwość i amplitudę drgań wymuszonych belki kompozytowej z cieczą magnetyczną. Na podstawie wyników obliczeń stwierdzono, że aktywacja cieczy magnetycznej spowodowała 10-krotne zmniejszenie amplitudy drgań, przy której występuje amplituda maksymalna.

EN

In the paper harmonic analysis of a sandwich beam with magnetic fluid (MR) is undertaken with the ANSYS program. The purpose of this analysis is to simulate a MR sandwich beam to obtain its natural frequency and vibration amplitude with and without magnetic field. The beam is made out of the polyethylene terephthalate and the used MR fluid is AL 458, produced by Fraunhofer-ISC. The viscoelastic properties of the fluid, needed for calculations, were obtained with a plate-plate Anton Paar rheometer which has an adapted MR fluid device to generate a uniform and controlled magnetic field up to 1 Tesla in the fluid gap. From these measurements, the complex shear modulus G* was inputted in the ANSYS program to model the fluid as a viscoelastic solid. This parameter was introduced as frequency-dependent properties. For the harmonic analysis, a sinusoidal load of 13N was applied to the beam in the vertical direction. Then, the plot response vs. frequency was obtained. It have been noted that application of magnetic field caused significant influence on amplitude decreasing. In conclusion it was stated that MR fluid can be successfully applied in sandwich beams, but results of numerical calculation should be verified experimentally before practical application.

5

Study on new float polishing with the MCF

63%

Shimada K. , Matsuo Y. , Yamamoto K. , Zheng Y.

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2007

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tom Vol. 23, nr 2

91-94

EN

Purpose: As a continuation of a previous paper, the report demonstrates the various possibilities of float polishing utilizing the present improved magnetic compound fluid (MCF). The MCF developed by one authors, Shimada, in 2001, was improved by the addition of alpha-cellulose, thereby achieving a clearance as great as 8 mm as shown in another paper. The present paper describes the possibility of the application of the MCF float polishing technique with alpha-cellulose. Design/methodology/approach: First, the results obtained under various polishing conditions of the MCF float polishing technique are described. These conditions include the various shapes of the magnet employed in the polishing tool, magnetic field strength, the concentration of alpha-cellulose, the motion of the specimen, the existence of a magnet fixed underneath the polished specimen, and initial surface roughness. Secondly, the present MCF float polishing technique can be used in many types of polishing, including polishing the inner surface of an acrylic resin tube, a wide flat surface through the use of a orbital polishing tool, and simultaneous float polishing of all surfaces of a three-dimensional complex shape. In addition, as other examples, the polishing on the integrated circuit (IC) substrate is shown. Findings: By the various polishing conditions of the MCF float polishing technique, the polishing effect is changed. On the other hand, as for the many applications of the MCF float polishing, inner surface, wide flat surface, rough initial surface, three-dimensional complex shape and IC substrate can be polished. Research limitations/implications: The data under various polishing conditions of the MCF float polishing technique helps to clarify the present polishing technique's possible practical applications. As shown in a previous paper, since MCF contains long magnetic clusters, the present polishing technique allows float polishing with large clearance. Therefore, many applications of the MCF float polishing are useful in the polishing fields. Practical implications: The present study indicates the practical application in the polishing. Originality/value: The present technique of MCF float polishing is new in the field of float polishing. In addition, the ordinary float polishing technique having large clearance has not been proposed. Therefore, the present paper is very useful in the polishing field.