Vliv paměťové funkce maziva v kluzných ložiskách na jejich dynamické vlastnosti

The influence of memory effects of journal bearing lubricant on its dynamics behavior

článek ve sborníku ve WoS nebo Scopus

en

The basic mathematical model in our new presented approach, which is using the Navier-Stokes and continuity eqs., is the wave equation. It will be shown in our contribution that for some cases this mathematical model is the same as the Reynolds eq. The composition of the differential equations for ideal and real, compressible and incompressible liquids will be shown in this paper. A totally new approach for its solution will be presented. It allows the determine of the liquid films added coefficients matrices by using only one parameter, in this case on the shaft center position. In the most general case includes the following added coefficients matrices: mass, damping and stiffness. Our new approach to the differential eqs. solution is called the complete solution, which also includes other time dependent parts. They are not taken into account in contemporary approaches. The Laplace transformation, which allows the analysis of both the frequency or time domain, is the base of our new approach. The reverse Laplace transformation includes time dependent parts, which represent the memory effects.

Příspěvek se zabývá přehledem některých metod pro analýzu dynamických vlastností tenkých tekutinových vrstev. technickými aplikacemi jsou kluzná ložiska, hydrodynamické tlumiče, případně těsnící spáry. Podstatou nových metod je možnost vzájemné separace pohybu tuhého tělesa (hřídele) a tekutiny. Vzájemná separace dále umožňuje tvorbu databáze přídavných účinků, které jsou funkcí pouze jednoho parametru, kterým je poloha středu hřídele. Dynamické vlastnosti se budou týkat analýzy rychlostního a tlakového pole a přídavných účinků od tekutinového filmu. Nové metody jsou aplikovány na stlačitelnou i nestlačitelnou tekutinu a pro analýzu v časové i frekvenční oblasti. Aplikace metod bude ukázána na modelových úlohách.

The basic mathematical model in our new presented approach, which is using the Navier-Stokes and continuity eqs., is the wave equation. It will be shown in our contribution that for some cases this mathematical model is the same as the Reynolds eq. The composition of the differential equations for ideal and real, compressible and incompressible liquids will be shown in this paper. A totally new approach for its solution will be presented. It allows the determine of the liquid films added coefficients matrices by using only one parameter, in this case on the shaft center position. In the most general case includes the following added coefficients matrices: mass, damping and stiffness. Our new approach to the differential eqs. solution is called the complete solution, which also includes other time dependent parts. They are not taken into account in contemporary approaches. The Laplace transformation, which allows the analysis of both the frequency or time domain, is the base of our new approach. The reverse Laplace transformation includes time dependent parts, which represent the memory effects.

Navier-Stokes eq., Reynolds eq., Compressible liquid, Laplace transformation, Journal bearings, Dynamics behavior

2006

25.09.2006

TU Vienna

Vienna, Austria

3-200-00689-7

7th IFToMM-Conference on Rotor Dynamics

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