Characterization of RAL bipedal robot capacitive MEMS accelerometer using electrical impedance measurements

Electrical Impedance Based Characterization of Wettability During Electrostatic Suppression of the Leidenfrost State

ASME 2019 Heat Transfer Summer Conference ◽

10.1115/ht2019-3426 ◽

2019 ◽

Author(s):

Onur Ozkan ◽

Vaibhav Bahadur

Keyword(s):

Heat Transfer ◽

Electrical Impedance ◽

Statistical Nature ◽

Impedance Measurements ◽

Threshold Voltages ◽

Different Temperatures ◽

Order Of Magnitude ◽

Wetted Area ◽

Impedance Characterization

Abstract An electric field can suppress the Leidenfrost state by electrostatically attracting liquid to the surface, which results in significantly higher heat transfer. This study highlights and quantifies the statistical nature of wetting during electrostatic suppression via electrical impedance characterization of Leidenfrost pools. Firstly, electrical impedance characterization is used to study the onset of suppression of the Leidenfrost state. Two different threshold voltages are defined and measured. The first threshold voltage corresponds to the onset of transient (intermittent) wetting and the second threshold corresponds to the onset of continuous wetting. The effect of the temperature and the applied AC waveform frequency on the threshold voltages is studied. Next, the wetted area is measured for different temperatures and voltages. The statistical nature of wetting during electrostatic suppression of the Leidenfrost state is characterized. The measured wetting enhancement indicates that heat transfer can be enhanced by an order of magnitude via electrostatic suppression. Together, these results provide an in-depth understanding of electrostatic suppression, and highlight electrical impedance measurements as a powerful diagnostic tool for this field.

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Imaging and functional characterization of crop root systems using spectroscopic electrical impedance measurements

Plant and Soil ◽

10.1007/s11104-018-3867-3 ◽

2018 ◽

Vol 435 (1-2) ◽

pp. 201-224 ◽

Cited By ~ 11

Author(s):

Maximilian Weigand ◽

Andreas Kemna

Keyword(s):

Electrical Impedance ◽

Functional Characterization ◽

Root Systems ◽

Impedance Measurements ◽

Crop Root

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Spark plasma sintering and characterization of bulk nanostructured fully stabilized zirconia: Part II. Characterization studies

Journal of Materials Research ◽

10.1557/jmr.2004.0424 ◽

2004 ◽

Vol 19 (11) ◽

pp. 3263-3269 ◽

Cited By ~ 49

Author(s):

U. Anselmi-Tamburini ◽

J.E. Garay ◽

Z.A. Munir ◽

A. Tacca ◽

F. Maglia ◽

...

Keyword(s):

Fracture Toughness ◽

Spark Plasma Sintering ◽

Electrical Impedance ◽

Sintering Temperature ◽

Impedance Measurements ◽

A Value ◽

Plasma Sintering ◽

Spark Plasma ◽

Characterization Studies

Dense fully stabilized cubic zirconia, sintered by the spark plasma sintering (SPS) method, was characterized through hardness, fracture toughness, and electrical impedance measurements. The effect of sintering temperature on hardness and fracture toughness was evaluated. Samples sintered at 1200 °C for 5 min, which had crystallite size of <100 nm, exhibited the highest hardness. Impedance measurements showed an increase in bulk contribution relative to grain boundaries as sintering temperature is increased. Calculation of the activation energy for conduction gave a value, 1.13 eV, in agreement with previously published results.

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