The influence of ferromagnetic fluids on performance of hydrodynamic bearings

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989100%3A27230%2F19%3A10243603" target="_blank" >RIV/61989100:27230/19:10243603 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/61989100:27740/19:10243603

Výsledek na webu

<a href="https://www.jvejournals.com/article/20950" target="_blank" >https://www.jvejournals.com/article/20950</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.21595/vp.2019.20950" target="_blank" >10.21595/vp.2019.20950</a>

Jazyk výsledku

angličtina

Název v původním jazyce

The influence of ferromagnetic fluids on performance of hydrodynamic bearings

Popis výsledku v původním jazyce

The rotors are often mounted in hydrodynamic bearings. To achieve their optimum performance in a wide range of operating speeds, their stiffness and damping parameters must be adaptable to the current angular velocity. This is offered by application of smart fluids sensitive to a magnetic field. The detailed analysis shows that application of ferromagnetic fluids is possible only for small sliding bearings. For bearings, the operation of which requires to generate high pressure, this concept fails. This arrived at the idea to use the ferrofluids-based magnetorheological fluids as a lubricant. This paper deals with the development of a basic concept of such a bearing and with the principle considerations on the magnetic flux generation and its propagation in the bearing housing and the lubricating layer. The developed mathematical model of the bearing was applied for investigation of the influence of changes of the lubricant properties by means of a magnetic field on the vibration attenuation of a rigid rotor excited by unbalance. The pressure distribution in the bearing gap is governed by the Reynolds equation adapted to non-Newtonian lubricant, the yielding shear stress of which depends of magnetic induction. The magnetic flux propagation in the bearing housing is described by the Hopkinson law. The results of the simulations show that the increase of the yielding shear stress of the lubricant by action of a magnetic field rises the bearing load capacity and does not destabilize the rotor vibration. (C) 2019 Jaroslav Zapoměl, et al.

Název v anglickém jazyce

The influence of ferromagnetic fluids on performance of hydrodynamic bearings

Popis výsledku anglicky

The rotors are often mounted in hydrodynamic bearings. To achieve their optimum performance in a wide range of operating speeds, their stiffness and damping parameters must be adaptable to the current angular velocity. This is offered by application of smart fluids sensitive to a magnetic field. The detailed analysis shows that application of ferromagnetic fluids is possible only for small sliding bearings. For bearings, the operation of which requires to generate high pressure, this concept fails. This arrived at the idea to use the ferrofluids-based magnetorheological fluids as a lubricant. This paper deals with the development of a basic concept of such a bearing and with the principle considerations on the magnetic flux generation and its propagation in the bearing housing and the lubricating layer. The developed mathematical model of the bearing was applied for investigation of the influence of changes of the lubricant properties by means of a magnetic field on the vibration attenuation of a rigid rotor excited by unbalance. The pressure distribution in the bearing gap is governed by the Reynolds equation adapted to non-Newtonian lubricant, the yielding shear stress of which depends of magnetic induction. The magnetic flux propagation in the bearing housing is described by the Hopkinson law. The results of the simulations show that the increase of the yielding shear stress of the lubricant by action of a magnetic field rises the bearing load capacity and does not destabilize the rotor vibration. (C) 2019 Jaroslav Zapoměl, et al.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20301 - Mechanical engineering

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Vibroengineering Procedia

ISBN

—

ISSN

2345-0533

e-ISSN

—

Počet stran výsledku

6

Strana od-do

133-138

Název nakladatele

JVE International

Místo vydání

Kaunas

Místo konání akce

Leipzig, Germany

Datum konání akce

30. 9. 2019

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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