Výpočtové modelování frekvenčně závislých přídavných účinků při interakci tělesa s tenkým tekutinovým filmem

Computational Modelling of Frequency Dependent Additional Effects During Fluid Film Interaction with Structures

conference paper

en

This contribution is focused on the interaction of a rigid body with a thin fluid layer. Some technical applications are for example: long and short, cavitating or noncavitating journal bearings. The governing equations for this analysis are the Navier Stokes equation, and the continuity and boundary conditions. The theoretical basis of a new approach to the analysis of dynamic behavior of nonstationary motion in time and frequency domains is presented. This totally new approach is based on separating the shaft and liquid layer from each other. It is possible to establish, using this separation, a database of additional effects of fluid film for a single given shaft parameter, which can be the shaft center position. The Bézier body is used for approximating the geometrical configuration as well as the velocities and pressures. The governing equations for both the net method and method of control volumes are presented. Curvilinear co-ordinates are used for describing the geometrical configuration and perpendicular co-ordinates are used for solving velocities and pressures.

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

This contribution is focused on the interaction of a rigid body with a thin fluid layer. Some technical applications are for example: long and short, cavitating or noncavitating journal bearings. The governing equations for this analysis are the Navier Stokes equation, and the continuity and boundary conditions. The theoretical basis of a new approach to the analysis of dynamic behavior of nonstationary motion in time and frequency domains is presented. This totally new approach is based on separating the shaft and liquid layer from each other. It is possible to establish, using this separation, a database of additional effects of fluid film for a single given shaft parameter, which can be the shaft center position. The Bézier body is used for approximating the geometrical configuration as well as the velocities and pressures. The governing equations for both the net method and method of control volumes are presented. Curvilinear co-ordinates are used for describing the geometrical configuration and perpendicular co-ordinates are used for solving velocities and pressures.

Navier-Stokes equation computational modelling, nonstationar analysis, journal bearings, additional mass, damping, stiffness

Navier-Stokes equation computational modelling, nonstationar analysis, journal bearings, additional mass, damping, stiffness

2004

01.09.2004

Mechanical Engineering, London

1-86058-447-0

Vibration in Rotating Machinery

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