Measurement of Annular Flow for Drilling Engineering by Electromagnetic Flowmeter Based on Double-Frequency Excitation

<table class="figure-group"><tr class="fig-image" id="a"><td><object data="https://static-preview.hindawi.com/articles/js/volume-2019/4090632/figures/4090632.fig.002a.svgz" name="4090632.fig.002a" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(a) </b>Virtual current potential</td></tr><tr class="fig-image" id="b"><td><object data="https://static-preview.hindawi.com/articles/js/volume-2019/4090632/figures/4090632.fig.002b.svgz" name="4090632.fig.002b" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(b) </b>Virtual current potential contour and virtual current vector streamline</td></tr></table>

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Journal of Sensors

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Figure 2

Figure 2: Measurement of Annular Flow for Drilling Engineering by Electromagnetic Flowmeter Based on Double-Frequency Excitation 