In-line measurements of the physical and thermodynamic properties of single and multicomponent liquids

Authors: Hugo Bissig, Oliver Büker, Emmelyn Graham, Leslie Wales, Andreia Furtado, Sara Moura, Zoe Metaxiotou, Seok Hwan Lee, Sabrina Kartmann, Jarno Groenesteijn and Joost C. Lötters


Microfluidic devices are becoming increasingly important in various fields of pharmacy, flow chemistry and healthcare. In the embedded microchannel, the flow rates, the dynamic viscosity of the transported liquids and the fluid dynamic properties play an important role. Various functional auxiliary components of microfluidic devices such as flow restrictors, valves and flow meters need to be characterised with liquids used in several microfluidic applications. However, calibration with water does not always reflect the behaviour of the liquids used in the different applications. Therefore, several National Metrology Institutes (NMI) have developed micro-pipe viscometers for traceable inline measurement of the dynamic viscosity of liquids used in flow applications as part of the EMPIR 18HLT08 MeDDII project. These micro-pipe viscometers allow the calibration of any flow device at different flow rates and the calibration of the dynamic viscosity of the liquid or liquid mixture used under actual flow conditions. The validation of the micro-pipe viscometers has been performed either with traceable reference oils or with different liquids typically administered in hospitals, such as saline and/or glucose solutions or even glycerol-water mixtures for higher dynamic viscosities. Furthermore, measurement results of a commercially available device and a technology demonstrator for the inline measurement of dynamic viscosity and density are presented in this paper.

Published by
De Gruyter

Publishing date
10. November 2022

Link to the document

(nur in Englisch verfügbar)

Other articles that might interest you

Article: Multiparameter Gas-Monitoring System

Article: Multiparameter Gas-Monitoring System

The aim of the study is to develop a compact, robust and maintenance free gas concentration and humidity monitoring system for industrial use in the field of inert process gases. Our multiparameter gas-monitoring system prototype allows the simultaneous measurement of the fluid physical properties (density, viscosity) and water vapor content (at ppm level) under varying process conditions.

Applications that might interest you

Monitoring of fuel concentrations
From volume (l) to mass (kg)
Monitoring of welding gas mixtures
Monitoring of gas mixtures for food packages