Design of a non-intrusive electrical impedance-based void fraction sensor for microchannel two-phase flows

作者：Valiorgue Pierre^*; Ritchey Susan N; Weibel Justin A; Garimella Suresh V

来源：Measurement Science and Technology, 2014, 25(9): 095301.

DOI：10.1088/0957-0233/25/9/095301

• microchannel
• two-phase flow
• void fraction
• impedance meter
• sensor design

A non-intrusive electrical impedance-based sensor is developed for measurement of local void fraction in air-water adiabatic flow through rectangular microchannels. Measurement of the void fraction in microchannels is essential for the formulation of two-phase flow heat transfer and pressure drop correlations, and may enable real-time flow regime control and performance prediction in the thermal regulation of high-heat-flux devices. The impedance response of the sensor to a range of flow regimes is investigated for a configuration with two aligned electrodes flush-mounted on opposing microchannel walls. Numerical simulations performed on a multi-phase domain constructed from three-dimensional reconstruction of experimentally observed phase boundaries along with the corresponding experimental results serve to establish the relationship between void fraction and dimensionless impedance for this geometric configuration. A reduced-order analytical model developed based on an assumption of stratified gas-liquid flow allows ready extension of these calibration results to different working fluids of interest.

• 出版日期2014-9