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Vortex throughflow measurement in steam

Two FHNW institutes developed a new measuring method for an innovative product manufactured by Endress+Hauser.

Durchflussmessgerät Prowirl


Development of a new measuring method for vortex flowmeters to determine steam quality.


Endress+Hauser is a leading global provider of instrumentation, services and solutions for industrial process engineering. It provides process solutions for flow, level, pressure and temperature measurement, analytical measurement, data logging and digital communication. In addition to the actual mass flow, a new product should also be able to determine the steam quality in steam flows.


The measuring principle of vortex flow measurement is based on the Kármán vortex street: Opposing vortices occur behind an obstacle. The volume flow is directly proportional to the frequency of the vortices. With the aid of pressure and temperature, the density of the medium and thus the mass flow can be calculated in the device. The actual vortex signal is evaluated in an ASIC developed at the Institute for Sensor Technology and Electronics FHNW in cooperation with Endress+Hauser. The Institute for Thermal and Fluid Engineering FHNW developed the metrological evaluation algorithms for the determination of steam quality and tested the measuring method on the specially constructed steam test facility. No other vortex flowmeter on the market today (as of 06/2019) can determine steam quality. A real innovation for Endress+Hauser customers to monitor their steam processes, developed in cooperation between FHNW and Endress+Hauser Flowtec AG.



Endress+Hauser AG


Institute for Sensors and Electronics, Institute of Thermo- and Fluidengineering

Research Sponsor

Innosuisse (Kommission für Technologie und Innovation KTI)


Prof. Dr. Hanspeter Schmid
Prof. Dr. Hanspeter Schmid Lecturer for Microelectronics and Signal Processing
Telephone +41 56 202 75 34 (direct)