Engineering & Technologies, Vol 6, No 6 (2013)

Numeric-analytical method for determining the communication equations of Laplace’s transformants of the universal radial unit of externally-pressurized gas bearings

Vladimir A. Kodnyanko

Abstract


The paper proposes a numeric-analytical method for determining the communication equations of Laplace’s transformants of dynamic functions of the universal unit of radial externally-pressurized gas bearings which movable element makes small radial oscillations in the locality in its central position. Method and obtained dependences provide links between integro-differential Laplace’s transformants of the unit such as load capacity and local input and output mass flow rates with transformants of eccentricity and gas lubricant pressure at inlet and outlet of the unit. It is shown that the local transfer functions of the unit model are rational functions of the Laplace’s transform variable and all such functions have a common denominator in the form of a polynomial of this variable. The method allows to calculate the required dynamic criterion of gas bearings containing this unit with prescribed accuracy. Founded dependences give ready formulas for calculation dynamic criteria of radial single-row or multi-row ordinary passive or active externally-pressurized gas bearings in which this unit can be used for description of radial movement of its movable element.