E.J. van der Wouden

Integrated multi-parameter flow measurement system

We have designed and realized an integrated multiparameter flow measurement system, consisting of an integrated Coriolis and thermal flow sensor, and a pressure sensor. The integrated system enables on-chip measurement, analysis and determination of flow and several physical properties of both gases and liquids. With the system, we demonstrated the feasibility to measure the flow rate, density, viscosity, specific heat capacity and thermal conductivity of hydrogen, helium, nitrogen, air, argon, water and IPA.

Fully integrated microfluidic measurement system for real-time determination of gas and liquid mixtures composition

We have designed and realised a fully integrated microfluidic measurement system for real-time determination of both flow rate and composition of gas- and liquid mixtures. The system comprises relative permittivity sensors, pressure sensors, a Coriolis flow and density sensor, a thermal flow sensor and a thermal conductivity sensor. The composition of the mixture can be calculated from the physical properties - density, viscosity, heat capacity, thermal conductivity and relative permittivity - as measured by the integrated sensors in the system.

Quantification of electrical field-induced flow reversal in a microchannel

We characterize the electroosmotic flow in a microchannel with field effect flow control. High resolution measurements of the flow velocity, performed by micro particle image velocimetry, evidence the flow reversal induced by a local modification of the surface charge due to the presence of the gate. The shape of the microchannel cross-section is accurately extracted from these measurements. Experimental velocity profiles show a quantitative agreement with numerical results accounting for this exact shape. Analytical predictions assuming a rectangular cross-section are found to give a reasonable estimate of the velocity far enough from the walls.