Abstract:
A method for monitoring and/or measuring an, at least at times, two-phase medium flowing in a pipeline, and having a first phase, especially a gaseous first phase, with a first density and a second phase, especially a liquid second phase, having a second density different from the first density. The method is performed with a vortex flow measuring device, which has at least one measuring tube inserted into the pipeline, a bluff body and a vortex sensor. In such case, the vortex sensor includes a sensitive section that responds to pressure fluctuations, and that is arranged at least partially adjoining the wall of the measuring tube. In the method, a wall flow of a second phase of a two or more phase medium is detected by the vortex flow measuring device, when a measurement signal which contains characteristic features for an interaction of a wall flow of the second phase of a flowing medium flowing along a wall of the measuring tube with the sensitive section of the first vortex sensor is registered by the vortex sensor.
Abstract:
PROBLEM TO BE SOLVED: To provide a vibration measuring device for measuring the viscosity of a fluid, led inside a pipe which is constituted, at the same time, as being suited also for the measurement of mass flow rate and the density of the fluid, and to make the accuracy of viscosity measurements improved by means of a Coriolis mass flowmeter-densitometer. SOLUTION: The vibration measuring device includes a flow tube, having a lumen conducting a fluid which is clamped at an inlet end and an outlet end that can vibrate and which vibrates about a static position of rest, during operation to perform lateral deflections that cause periodic changes in the spatial position of the lumen. A sensor device forms a first sensor signal, representative of the inlet-side deflections of the flow tube, and a second sensor signal that indicates the outlet-side deflections of the flow tube; an excitation circuit forms exciting current, feeding an excitation arrangement. An evaluation circuit derives a density measured value that indicates the density of the fluid and derives a viscosity value that indicates the viscosity of the fluid, from at least one sensor signal and from the density measured value, on the basis of the excitation current. COPYRIGHT: (C)2008,JPO&INPIT