METHOD FOR DETERMINING AND/OR MONITORING VISCOSITY, AND CORRESPONDING APPARATUS

摘要

The invention relates to a method for determining and/or monitoring the viscosity of a medium (2). In said method, a unit (1) that can mechanically oscillate is excited to oscillate by means of an excitation signal, and the unit (1) receives oscillations and converts the same into a receive signal. The natural oscillation (w0) and/or the resonant frequency (wres) of the unit (1) that can oscillate and/or the phase angle between the excitation signal and the receive signal are determined and/or monitored. Conclusions about a change in viscosity are drawn from changes in the natural oscillation (w0) and/or the resonant frequency (wres) and/or the phase angle, and/or the viscosity is determined from the natural oscillation (w0) and/or the resonant frequency (wres) and/or the phase angle on the basis of correspondingly stored dependencies of the oscillations on the viscosity of the medium. In a second variant of said method, the damping behavior of the unit that can mechanically oscillate is evaluated. The invention further relates to an apparatus for determining and/or monitoring viscosity.