THEORY AND PRACTICE OF FLUID DAMPERS IN MACHINE TOOLS

In the first part the authors summarize the theory leading to practical formulae for computing the damping constants and the equivalent mass of liquid film dampers. The importance of the equivalent mass of the liquid film on the natural frequency of the systems is emphasized. Corrections are introduced for the border effect. The limits of the linear behaviour are discussed taking into account the cavitation due to vapour pressure, absorbed and free air in the oil. The order of magnitude of the different effects is shown with practical examples.