Abstract: A method for verifying a density and/or viscosity measuring device in a measuring station of a process installation during ongoing operation, in which a medium flows through a main channel of the process installation, comprising steps: providing a side channel, which is connected as a bypass of the main channel, wherein the side channel is fluidically connected to the main channel via two regions of the main channel with mutually differing diameters; providing a MEMS-based master or control density measuring device in the side channel such that the MEMS-based master or control density measuring device is flowed through by the medium; performing at least one verification measurement with the MEMS-based master or control density measuring device; and verifying the density and/or viscosity measuring device based on the at least one verification measurement performed by the MEMS-based master or control density measuring device.

Abstract: The present disclosure relates to a method for determining a volumetric and/or mass flow rate of a medium flowing in a tube, wherein a density and/or a viscosity of the fluid is/are determined using a MEMS sensor chip, wherein the medium flowing in the tube at least partially flows through a measuring channel of the MEMS sensor chip to determine the density and/or the viscosity of the fluid, and wherein the volumetric and/or mass flow rate of the medium is determined regardless of the medium based on a detected pressure drop over the measuring channel of the MEMS sensor chip and the density and/or viscosity determined by the MEMS sensor.

Abstract: A MEMS sensor for measuring at least one measured variable, especially a density, a flow and/or a viscosity, a flowing fluid, is described, comprising: at least one microfluidic channel having a channel section excitable to execute oscillations; and an exciter system for exciting a desired oscillation mode, causing the channel section to execute oscillations in a predetermined plane of oscillation. The MEMS sensor has improved oscillation characteristics at least in part because the channel section is composed of an anisotropic material, having directionally dependent elasticity and which is spatially oriented such that a modulus of elasticity determinative for a stiffness of the channel section relative to deflections of the channel section perpendicular to the plane of oscillation is greater than a modulus of elasticity determinative for a stiffness of the channel section relative to deflections of the channel section in the plane of oscillation.